hypothesis on music on plant growth

Playing Music For Plants – How Does Music Affect Plant Growth

We’ve all heard that playing music for plants helps them grow faster. So, can music accelerate plant growth, or this just another urban legend? Can plants really hear sounds? Do they actually like music? Read on to learn what experts have to say about the effects of music on plant growth.

Can Music Accelerate Plant Growth?

Believe it or not, numerous studies have indicated that playing music for plants really does promote faster, healthier growth. In 1962, an Indian botanist conducted several experiments on music and plant growth. He found that certain plants grew an extra 20 percent in height when exposed to music, with a considerably greater growth in biomass. He found similar results for agricultural crops, such as peanuts , rice , and tobacco, when he played music through loudspeakers placed around the field. A Colorado greenhouse owner experimented with several types of plants and various genres of music. She determined that plants “listening” to rock music deteriorated quickly and died within a couple of weeks, while plants thrived when exposed to classical music. A researcher in Illinois was skeptical that plants respond positively to music, so he engaged in a few highly controlled greenhouse experiments. Surprisingly, he found that soy and corn plants exposed to music were thicker and greener with significantly larger yields. Researchers at a Canadian university discovered that harvest yields of wheat crops nearly doubled when exposed to high-frequency vibrations.

How Does Music Affect Plant Growth?

When it comes to understanding the effects of music on plant growth, it appears that it isn’t so much about the “sounds” of the music, but more to do with the vibrations created by the sound waves. In simple terms, the vibrations produce movement in the plant cells, which stimulates the plant to produce more nutrients. If plants don’t respond well to rock music, it isn’t because they “like” classical better. However, the vibrations produced by loud rock music create greater pressure that isn’t conducive to plant growth.

Music and Plant Growth: Another Point of View

Researchers at the University of California aren’t so quick to jump to conclusions about the effects of music on plant growth. They say that so far there is no conclusive scientific evidence that playing music for plants helps them grow, and that more scientific tests are needed with rigorous control over factors such as light, water, and soil composition. Interestingly, they suggest that plants exposed to music may thrive because they receive top-level care and special attention from their caretakers. Food for thought!

Gardening tips, videos, info and more delivered right to your inbox!

Sign up for the Gardening Know How newsletter today and receive a free download of our most popular eBook "How to Grow Delicious Tomatoes."

A Credentialed Garden Writer, Mary H. Dyer was with Gardening Know How in the very beginning, publishing articles as early as 2007.

Useful links

Stay in touch.

Job Opportunities
Marketplace
Contact Future's experts
Terms and Conditions
Privacy Policy
Cookie Policy

Gardening Know How is part of Future plc, an international media group and leading digital publisher. Visit our corporate site . © Future US, Inc. Full 7th Floor, 130 West 42nd Street, New York, NY 10036.

Plant Answer Line
Garden Tours & Plant Sales

music and plant growth

How does music affect plant growth?

Washington State University professor of horticulture Linda Chalker-Scott uses the example of a book on the effect of music on plants as an instance of ‘bad science’ in one of her articles . In other words, the idea is not based on repeated experiments, and has not been put to the test of attempts to prove or disprove it. Many student science fair projects pursue this question. There are many other scientists discussing this, and sites on the topic, too.

The TV show Mythbusters Episode 23 has dealt with this question.

There are also two questions exploring this at the MadSci network, a scientist-staffed question site. Here is an excerpt from the MadSci network’s discussion: Experiments on the effects of sound or music on plants are very difficult because you need a lot of replication (number of plants for each treatment) and identical environments for each treatment other than the music or sound level. That is difficult to achieve even for a professional botanist much less in a home or classroom. You also need a statistical analysis to determine if the growth differences are real or just due to natural variability. No botanist has yet found a beneficial effect of music or sound on plant growth that is reliably repeatable and statistically significant.

The idea that plants grew better with certain kinds of music apparently arose in the best selling book, ‘The Secret Life of Plants.’ That book was filled with incorrect information. Botanists have failed to find that plants grow better or worse with a particular type of music or that music has any effect on plants. While the stories in ‘The Secret Life of Plants’ are intriguing, they are not based on careful scientific experiments. For accurate scientific details on plants try a college botany textbook (Stern, 1991) or popular books on plants written by scientists (Attenborough, 1995; Wilkins, 1988).

Attenborough, D. 1995. The Private Life of Plants . Princeton, NJ: Princeton University Press.

Stern, K.L. 1991. Introductory Plant Biology . Dubuque, Iowa: Wm. C. Brown.

Wilkins, M. 1988. Plantwatching: How Plants Remember, Tell Time, Form Relationships and More . New York: Facts on File.

Professor Ross Koning, who teaches Plant Physiology at Eastern Connecticut State University has addressed this question at length , too. Here is an excerpt from that site (now archived), as well:

“If plants don’t have music appreciation, do they respond to sound? It is possible for a plant to respond to the vibrations accompanying sounds. A short bibliography at the bottom of this page gives you some references…but to almost ‘nothing to report.’ I emphasize again that while there ARE responses to sound/vibration in plants, there is NO controlled study published on the MUSICAL TASTES or MUSIC APPRECIATION by plants in reputable journals.

One plant that responds to sound-induced vibration is Mimosa pudica, also known as the ‘sensitive plant.’ Vibrations induce electrical signals across the leaflets of this plant, and cells at the base of the leaflets respond to these action potentials osmotically. This response results in a sharp change in the turgor pressure in these pulvinus cells, and that pressure change, in turn, results in the folding of the blade at the pulvinus. Another pulvinus at the base of the petiole may also respond if the vibration is severe enough. This kind of response is known as seismonasty.

How would this plant respond in terms of growth if its leaves were kept closed by constant vibration? If you think very long about photosynthesis in leaves as the driving force for growth, you will realize that continuous leaflet closure would inhibit rather than stimulate the growth of the plant. Indeed loud sounds (vibrations really) have been reported to negatively impact plant growth (reference below).”

Pistils Studio
Mounted Plants

Pistils Mississippi

Corporate Gifting
Private Workshops

Should You Sing to Your Plants? Here's What the Science Says

Can plants enjoy music just as we do? And can listening to music help them develop? If so, maybe we're not so different as we seem. The possible correlation between exposure to music and the growth rate of plants is fascinating, and may perhaps allow for a new and deeper understanding about the living creatures surrounding us in our homes.

Music and plant growth has been a topic in the scientific community for quite some time. At Pistils, we found ourselves curious to find out what these studies show and what the people conducting them are saying about how music affects plants. As we started digging in to the research, we found that experiments involving music and plant growth in agriculture as well as in greenhouses have been conducted and seem to show that playing music actually promotes the growth of plants!

But it's not quite so simple, and there's still a bit of controversy around these findings. Here's a bit of what the studies say, simplified, and why some may disagree.

Music and Plant Growth

The science.

Unlike us humans, plants don’t have ears with which to hear sound. So how are they influenced by music? It’s not exactly that they are tapping their roots to the beat of a drum. Rather, sound waves stimulate the plant's cells. When the cells are stimulated by the sound, nutrients are encouraged to move throughout the plant body, promoting new growth and strengthening their immune systems.

Believe it or not, studies indicate that plants also seem have a specific taste in music! Some genres of music promote growth, whereas others can be damaging. Roses in particular seem to love violin music. For most plants playing classical or jazz music caused growth to increase, while harsher metal music induced stress. This may be because the vibrations of metal music are too intense for plants and stimulate cells a little too much.

We think of this like massaging your plant with a song – they prefer a gentler touch.

What Botanists Have to Say

Devendra Vanol of the Institute of Integrated Study and Research in Biotechnology and Allied Sciences in India found that not only does music promote plant growth, but it seems that plants can actually distinguish between different types of sound including different genres of music, nature sounds, and traffic noise. Vanol and her team say it could be advantageous for plants to distinguish sounds to learn about their surrounding environment. More studies need to be done to understand how this works and what this could teach us about plants.

According to Reda Hassanien of China Agricultural University in Beijing, sound waves significantly increased the yield of sweet pepper, cucumber, tomato, spinach, cotton, rice, and wheat. Additionally, pests such as spider mites, aphids, gray mold, late blight, and virus diseases of tomatoes decreased in greenhouse conditions with sound treatment. It is amazing what plants can do with a little bit of music playing in the greenhouse!

How can we use this new information? “The world population increase presents a challenge to scientists and researchers to investigate the possibilities for utilizing new and green technologies to increase the production of food," says Hassenien." Using sound waves technology can enhance the plant immune system thereby; avoiding many problems associated with the environmental pollution and the economic costs of chemical fertilizers and herbicide” (Hassanien 2014).

What if we could use music to promote plant growth instead of chemicals? Playing music for our agricultural crops could be the soothing sound of positive change in our food system.

Others believe that more research needs to be done in order to agree to establish a connection between music and plant growth. They say that plants in these studies are given special treatment, and further experiments need to be repeated with stricter control over growing conditions such as light, soil, and water.

Whether or not music promotes plant growth, we think that it couldn't hurt to play them a little jazz now and again, and some scientists and farmers around the world say it just might help them grow a little faster. So why not try putting on a soothing record the next time you water your plants?

We may not know for certain if music effects plant growth but one thing that is for sure is that treating your plants like the amazing living creatures that they are can help our green friends to be happier and healthier. Build a relationship with your house plants by talking to them with words of encouragement, give them a name, play them a song, love them and they will grow.

For the plant nerds among us that would like to dig deeper into the studies surrounding music and plant growth here are some free articles we recommend taking a peek at:

https://scholar.cu.edu.eg/sites/default/files/redagreen/files/advances_in_effects_of_sound_waves_on_plants.pdf
https://pdfs.semanticscholar.org/f3ef/50e5de86c302c09e2d1b11f0d3295143182b.pdf
http://aribas.edu.in/quest/2014/issue3/3.pdf

By: Brittany Oxford

This is AMAZING to me and I want to believe it. so I’m going to try it. I just happened upon this information. I think I was meant to find it.

This was very helpful! thank you! I believe that music does help plants :).

Music is vibration, vibration does not become music until it is processed by a conscious subject. Probably for plants vibration is simply vibration, and enjoys it for what it is, stimulus. Plants are stimulated by photons, the wind, moister, predators ,pollenators, fungi and who the hell knows what else. Don’t let the judgment of other blind you to wonder, it can be mind-numbing.

This has been thoroughly debunked. Any type of noise seems to produce similar results, be it any type of music including rock, punk, metal etc as well as other noise sources.

It sure was nice when you said that play plants a song and talking to them could encourage their growth. This sounds really interesting to me since I am planning to grow some plants at home. It could be ideal to find folk and rock songs that I can play at home. https://maryannsmusic.com/

I am frantic at the moment I ordered two lovely 4” staghorns ; they were tender and all green when they arrived but were pitted in soil when they came but this was a problem for me a I Wanted to place them( without pits or soul) onto the branches of a curly willow branch I display in my home. So I removed most o the soil wrapped roots in some burlap to suspend in my tree, I had to squeeze and manipulate the root ball trying t accomplish thus Sadly the little green fern is all wilted and drooping even though I misted and soaked the burlap before trying to place it in my branch! Have I killed it? What can or should I do or is it too late( theses staghorns are not the moose head or elk horn variety. Any advice really appreciated// am feeling like a murdress!

My husband often makes fun of me when he hears me give kind words to my plants as I water them. What living thing doesn’t benefit from love and kindness?

I first heard about this in the 1970’s while I studying horticulture, I read “The Secret Life of Plants”. It changed the way I view them. This also suggested they respond to our energy as well.

What a great article! Another reason to believe this life is not just a product of chance but of thoughtful and creative design.

Please note: comments must be approved before they are published.

3811 N Mississippi Ave Portland, OR 97227 (503) 288-4889

Store Hours Open Every Day 10am - 7pm — Pistils NW

2139 NW Raleigh St Portland, OR 97210 (503) 288-4889

Store Hours Open Monday-Friday 11am-6pm Saturday & Sunday 11am-7pm

Privacy Policy
Terms & Conditions
Cookie Policy

Sign up and save

Entice customers to sign up for your mailing list with discounts or exclusive offers.

Academia.edu no longer supports Internet Explorer.

To browse Academia.edu and the wider internet faster and more securely, please take a few seconds to upgrade your browser .

Enter the email address you signed up with and we'll email you a reset link.

We're Hiring!
Help Center

Different Genres of Music: The Effect on the Growth of Plants

Related Papers

Nikita Sharma

Plants are known to respond to stimuli and music is considered as one. It has been observed that different types of sound affect the health of plants differently. In this paper, the influence of acoustic frequencies including those of music on the growth pattern of plants as observed by many researchers have been reported. Besides, the authors have carried out a pilot study to observe the response of Tagetes sp. (marigold) to Light Indian Music and Meditation Music as well as to noise. They have also monitored the germination of Cicer arietinum (chickpea) on exposure to Light Indian Music. It could be commented that music promoted the growth and development of the plants, including germination whereas noise hindered it. Possibly, specific audible frequencies and also musical frequencies facilitate better physiological processes like absorption of nutrients, photosynthesis, protein synthesis, etc. for the plant and this is observable in terms of increased height, higher number of leaves and overall more developed and healthier plants.

International Journal of Plant, Animal and Environmental Sciences

Hitesh A Solanki

This study was an attempt to understand the effect of music on plant growth and development. Eight medicinal and ornamental plants were selected for the study. Two sets of selected plants were prepared, one of them was subjected to rhythmic soft-melodious music, and a control set of plants was not exposed to any particular music. Music was played for fixed period for a month. After the treatment various growth and physiological parameters of treated plants were studied against the control plants. From the results, it was observed that plant growth in treated plants was better than control plants with treated plants especially showing increased level of various metabolites. Key words: Soft-melodious music, plant metabolites.

INTERNATIONAL JOURNAL OF PLANT AND ENVIRONMENT

Dipal Bhatt

Music can trigger a range of emotions in humans and other animals. It also has some beneficial effects on plant growth. Music isregarded as one of the triggers to which plants are known to respond. Plants respond to different types of music. They grow well whenexposed to certain kinds of music, whereas there may have stunted growth with another type of music. This may differ depending onthe kind of plant species also. It could be said that noise inhibited plant growth and development, whereas music encouraged it, evengermination. Certain audible and musical frequencies aid the plant in improving physiological processes, including nutrient absorption,increased protein content, etc. This is evident in the plant’s growth in terms of height, number of leaves, and general development andhealth. Some scientific researchers have proved that the growth of plants can be influenced by music and the farmers can use this forbetter growth of plants

Katherine Creath

Cyros Aris Mayor

Specific musical work as a physical inducer and growth stimulator in romaine lettuce (Atena Editora)

Atena Editora

Para el año 2050 se estima un aumento de la población cercano a los 9 700 millones de personas, por lo tanto la demanda de alimento aumentará y el espacio para cultivo disminuirá. Las ondas sonoras tienen un estímulo y efecto sobre las plantas, este tipo de elicitores mejora las condiciones de crecimiento, metabolismo energético, expresión génica relacionada con el estrés, incrementa metabolitos secundarios y resistencia a enfermedades. El objetivo de esta investigación es tener un estudio preliminar para promover la exposición sonoro musical en los cultivos y eficientar su crecimiento. Los resultados indicaron una reducción en el tiempo de cosecha a 10 semanas en comparación del grupo control que se cosecharon en 13 semanas, al ser expuestas a 2 composiciones específicas durante todo su ciclo. Lo que representó un incremento del 28.57% en la producción.

Avdhoot Kotkar

This project is intended to show how the rate of growth of two different plant species was affected by sounds of varying frequencies. Two plant species, beans and impatiens, were selected because of their rel atively fast growing rates. Ambient conditions were regulated by environmental chambers in which the plants were housed. One chamber was used as a control for the plants, and the plants in the other chambers were subjected to sounds of different frequencies at roughly the same sound intensity. Sounds of pure tones and random [wide band] noise were used. The changes in the growth of the plants were monitored every two days for twenty-eight days. Upon completion of the tests, it was observed that optimum plant growth occurred when the plant was exposed to pure tones in which the wavelength coincided with the average of major leaf dimensions. It is suggested that this was due to the " scrubbing " action of the traversing wave, causing air particle motion on the surface of the leaf; this movement removed the stagnant air layer adjacent to the leaf, thus increasing the transpiration of the plant. It was also noted that the plant growth was less when exposed to random noise. SOMMAIRE Ce project avait pour but de montrer comment le taux de croissance des deux espèces de plantes être influé par une variété d'ondes sonores. Les deux espèces, des haricots et des impatiens, ont été choisis à cause de leur croissance rapide. Les plantes furent placées dans des sailles donc les conditions ambiantes étaient réglées selon les critères environnmentales. Une salle servit de contrôle pour les plantes. Dans les autres salles, les plantes furent exposées à divers ondes sonores d'environnment à la même intensité. Des ondes sonores claires et croissant au hazard furent difusées. Les taux de croissance furent servi des près. C'est à dire, à tout les deux jours jusqu' au visit-huitième jour. A la fin de ces tests, nous avons observé été la crois sance optimum a eu lieu dans les plantes exposées aux ondies sonores claires, et que la longeur des ces ondes coincidait avec la dimension moyenne des feuilles. On suggère que ceci s'est produit quand les ondes sonores ont " balayé " les particules dans l 'air sur la surface de la feuille. Ce déplacement d'air stagnnat attenant la feille permet ensuite à celle-ci d'augmenter la transpiration végétale. Aussi, nous avons observé une baisse de croissance dans les plantes exposées aux ondes sonores choisies au hazard.

Jurnal BETA (Biosistem dan Teknik Pertanian)

Arya Arthawan

The photosynthesis process in indoor cultivation system does not get optimal sunlight, therefore LEDs can be used as artificial light. The red-blue color is a color that has a positive effect on plant growth. In addition, to increase the rate of photosynthesis, one of the technology advances that can be used is sonic bloom. Sonic bloom is the delivery of high-frequency sound waves in plants to stimulate the opening of the leaf stomata mouths which is accelerating the rate of absorption of carbon dioxide, water and soil minerals. In this study, Pakcoy was exposed to jazz music to determine the effect on production of Pakcoy, and the best length of exposure. The length of exposure to jazz music was 1 hour, 2 hours, 3 hours, 4 hours, and 5 hours starting from 07.00 WITA. The type of jazz music used was Jazz Rock with the musical instrument Gambandella by Psychedelic Jazz-Rock Fusion with a frequency of 86 – 21189 Hz and a sound intensity of 65-95 dB. In the growth chamber, artificial l...

Simone Vitale

The Music of the Plants project aims at investigating, in an artistic way, the reactivity of plants to their environment and their ability to communicate and learn. This research has not yet entered mainstream scientific investigation, so all the information available is offered by communities and individuals that, like myself, can see the meaning in terms of ethical, ecological and spiritual awareness. We can improve our relationship with our environment by understanding the presence of something we can call "consciousness" in plants.

Galih Braga

RELATED PAPERS

Raden Mas Cozar

Reproductive BioMedicine Online

David Bruce Sable

Biochimica et Biophysica Acta (BBA) - Biomembranes

Christophe Ramseyer

Nick Krekelbergh

South American Journal of Basic Education, Technical and Technological

Eglieni Trevezani

The Journal of the Acoustical Society of America

Antonio Cantoni

Jelita Hutapea

nives licen

Archivos Argentinos de Pediatria

MARINA ORSI

Jurnal Ilmu Tanah dan Lingkungan

Harisman Edi

Revista Española de Geriatría y Gerontología

Luis Eduardo Charris Guerra

Texas Heart Institute journal / from the Texas Heart Institute of St. Luke's Episcopal Hospital, Texas Children's Hospital

Alev Kızıltaş

ImrulHossen Chowdhury

Belvedere Meridionale

Vivien Bondea

IEEE Transactions on Circuits and Systems I: Regular Papers

Antibiotics

Coccia Mario

Journal of Pharmaceutical Research International

maryam fatima

Infectious Diseases Now

Celine Chasport

The Journal of Immunology

Is There a Role for Sound in Plants?

Associated data.

Not applicable.

Plants have long been considered passive, static, and unchanging organisms, but this view is finally changing. More and more knowledge is showing that plants are aware of their surroundings, and they respond to a surprising variety of stimuli by modifying their growth and development. Plants extensively communicate with the world around them, above and below ground. Although communication through mycorrhizal networks and Volatile Organic Compounds has been known for a long time, acoustic perception and communication are somehow a final frontier of research. Perhaps surprisingly, plants not only respond to sound, they actually seem to emit sound as well. Roots emit audible clicks during growth, and sounds are emitted from xylem vessels, although the nature of these acoustic emissions still needs to be clarified. Even more interesting, there is the possibility that these sounds carry information with ecological implications, such as alerting insects of the hydration state of a possible host plant, and technological implications as well. Monitoring sound emissions could possibly allow careful monitoring of the hydration state of crops, which could mean significantly less water used during irrigation. This review summarizes the current knowledge on sound perception communication in plants and illustrates possible implications and technological applications.

1. Introduction

Plants have been around for a long time, far longer than Homo sapiens . Homo sapiens arose approximately 300,000 years ago [ 1 ], a minimal length of time compared with the age of Earth. The earliest land plants, on the other hand, first appeared in the fossil record millions of years prior to this. Non-vascular plants such as the true mosses, the Bryopsida, for example, first appeared in the Mississippian 340 million years ago and appeared well established by the Permian. However, the earliest bryophytes in the fossil record already have the basic thallus organization possessed by current forms, suggesting the possibility that the bryophytes evolved even earlier than the fossil record suggests [ 2 ]. Baragwanathia, which is a relatively complex vascular plant, was confirmed to be of Late Silurian origin, which was approximately 420 million years ago [ 2 ]. Fossils of the first flowering plants date back to around 130 million years ago, a milestone not only for their role in the evolution of plants but also for the relationship of plants with insects [ 3 ]. The appearance, enormous diversification, and ecological radiation of the angiosperms began during the Cretaceous, between 135 to 65 million years ago, and it represented a very significant alteration to the history of life on Earth. It had vast repercussions on the distribution of other groups of land plants and a great effect on the evolution of ecosystems and species. Today, there are more than 350,000 species of extant angiosperms, which is more than all the other groups of land plants combined [ 4 ]. They occupy and dominate an astounding range of habitats, and -as autotrophs- the angiosperms are the base upon which most ecosystems are built [ 4 ].

Plants are sessile and photoautotrophic, which means that they produce new biomass from CO 2 using light energy in a process called photosynthesis. Most of the energy that enters terrestrial habitats is the result of photosynthesis. Plants are so important that they go so far as to influence the atmosphere and climate, and yet at the same time, the environment itself has a profound impact on photosynthesis and plants.

And therein lies the point. Plants are not passive organisms, though their sessile nature might make them appear to be static or unchanging. Though plants have an awe-inspiring impact on most life on earth, most people tend to underappreciate or not notice the plants living around them. Plants are alive, and like all things that are alive, they perceive many environmental and physiological signals, and through these, they perfect and modify their growth and development. Not only that, but recent scientific studies have also shown that plants are capable of exhibiting learning, memory, and even intelligence (although maybe not consciousness) [ 5 , 6 , 7 , 8 ]. It is reasonable to assume that plants have evolved to do so. After all, as stated before, land plants first appeared millions of years ago. As new plant forms evolved, so did the capacity to perceive stimuli and adapt to a changing environment [ 9 ].

But plants do much more than just perceive and react. Plants communicate amongst themselves and with animals. Plants do so in many ways, both above and below ground; a growing body of research shows that plants can even detect and emit sounds (for a review, see [ 10 , 11 ]).

2. Communication through Sound

A growing body of research is showing that plants detect and emit sounds. This is unsurprising considering that there is no habitat colonized by plants that is without sound and taking into account their sessile nature and their age on Earth, it is reasonable to think that they have learned to do so.

2.1. What Is “Sound”

Briefly, sound is defined as a series of longitudinal waves of pressure that propagate through compressible media, such as air, liquids, or solids. Sound waves that fall in the range of frequencies between 20 Hz and 20 kHz belong to the audible sound, which is what a human ear can hear; frequencies below 20 Hz or higher than 20 kHz are defined as infrasound or ultrasound, respectively [ 12 ]. However, sound is not only vibration energy; it is also pressure generated by vibration waves that move through a suitable medium in the form of compression and rarefaction [ 12 ]. For a sound to be perceived, however, it is not sufficient that it consists of frequencies in the audible range; it must also have sufficient sound pressure, that is, the pressure variation produced by the acoustic phenomenon compared with the static value. For example, in the air a sound pressure of 20 µPa corresponds to a level of sound pressure of 0 dB [ 13 ].

Application of sound at different frequencies, pressure levels, duration, and repetition of exposure periods has been proved to have an influence on plant growth, development, and germination [ 10 ]. Taken together, these studies belong to the field of Plant Acoustics. Whether or not sound perception and/or emission are used in plant communication is a fascinating field of research. However, for acoustic plant communication to exist, there needs to be an emitter, in other words, a source of sound and a receiver not only able to perceive the signal but also able to decipher and eventually perform a sort of coherent response.

Sound stimulation has been proven to switch on stress-induced genes [ 14 ] or enhance genes related to disease resistance [ 15 ], but there is also a sort of new age interest in growing plants with sound. Traditional ethnic music can positively affect the productivity and quality of plants. Many studies are heading in that direction: Javanese music has been applied to Chinese broccoli ( Brassica alboglabra ) plants [ 16 ], and Desmodyium girans (Telegraph plant) [ 17 ] and rice ( Oryza sativa ) [ 18 ] show better growth performance when exposed to Buddhist pirith chants.

2.2. Sound at Cellular and Subcellular Level

On a cellular level, it seems that the most likely candidate for sound signaling is Ca 2+ , which acts as a second messenger to Sound Vibrations (SVs). Although direct evidence is lacking, it is possible that SVs activate plasma membrane channels, evoking a membrane potential-based signaling cascade. Several studies have shown an efflux/influx of Ca 2+ following SVs. It was shown, for example, that Chrysanthemum cells treated for one hour with SVs of 100 dB and 1000 Hz had an increase in H + -ATPase activity [ 19 ]. The upstream component of this increased activity was found to be Ca 2+ . It appears that transient increases in cytosolic Ca 2+ concentrations lead to an activation of calcium-dependent protein kinases, which then activate the H + -ATPases. These kinases go on to regulate proteins and transcription factors, therefore altering gene expression [ 20 , 21 , 22 , 23 ]. For example, after treatment with SVs, plant cells showed increases in α-amylase activity and as a result, an increase in sugar levels. ROS scavenging enzymes have been shown to increase activity after SV treatment, and overall, the most common plant response to SV treatment is increased growth, for example, through increased cell division. All this, however, is just a general overview of what happens at the cellular level following sound perception, and it is well described in greater detail by Mishra and co-workers in 2016 [ 23 ].

But there is another side to the coin. Sound is generated by vibrating objects, and the components of eukaryotic cells do just that. Following the hydrolysis of Adenosine triphosphate (ATP), motor proteins such as myosin generate vibrations [ 24 ]. In addition, the nanomechanical motions of the cell wall of Saccharomyces cerevisiae , baker’s yeast, are in the range of 800–1600 Hz, with amplitudes of 3 nm. Interestingly, exposing the cells of S. cerevisiae to a metabolic inhibitor caused the periodic motion to cease [ 25 ]. Cells are surrounded by other cells so that a cell can be influenced by the mechanical properties of its adjacent cells, and this can build up to a collective mode which results in amplification of the signal [ 24 ].

2.3. Sound like Touch

Sound and touch have similar physical properties, and yet plants cannot only properly distinguish between sound and touch, but they are also able to distinguish between relevant and irrelevant sound. The ability of plants to perceive touch has been well known for a long time. One need only to look at the carnivorous plant Dionaea muscipula or at Mimosa pudica to see plants reacting to touch. Since sound is generated by a vibrating body, and it propagates longitudinally by vibrating the particles of the medium, it passes through, when it reaches a body, it vibrates the body mechanically as well. In other words, sound waves mechanically impact an object they meet on their path [ 9 ].

The molecular basis for the perception of a mechanical stimulus in plants remains to be identified. However, touch sensitivity is not just limited to sensitive plant and carnivorous species. Every plant (or plant cell) perceives and accordingly responds to mechanostimulation [ 26 ]. Even plant roots are extremely sensitive to touch, being able to turn around an obstacle in their path. Like wind, light, rain, touch, sound is a pressure wave that translates into a mechanical influence. For the perception of a mechanical stimulus in plants, Telewski suggested a “unified hypothesis of mechanoperception in plants” [ 27 ] with two models of mechano-receptors: (a) a cytoskeleton based on plasmodesma—plasma membrane—cellular network and (b) ion channels activated by stretching. Given the similarity of the sound stimulus to that of touch, it has recently been seen that signals and perception mechanisms of these two stimuli are common. However, the plants seem to distinguish between the two well in an extraordinarily sophisticated way [ 26 ].

3. Effects of Sound Perception

Human conversation typically has an intensity of approximately 60 dB, and at this intensity, it can elicit vibrations, for example, in hearing organs, of just 10–50 nm. At these scales, the mechanical energy imparted by the vibrations is exceedingly small, and yet we have no problems hearing during conversation. Considering this, it really is reasonable to think that something as small as a trichome could vibrate in response to SVs and possibly convey information [ 28 ].

In much the same way plants have adapted to different pollinators, plants have adapted to different sounds in their environments. For example, flower morphology affects the efficiency of pollinators, affects the way pollinators visit flowers and the success of pollen import and export [ 29 ]. Similarly, the carnivorous pitcher plant Nepenthes hemsleyana could possibly have evolved pitchers that reflect the echolocation of bats. The plant N. hemsleyana has a mutualistic interaction with bats, supplying a safe, parasite-free roosting spot, and the bats in return fertilize the plant with nitrogen-rich droppings, enhancing the nitrogen uptake of these plants by an average of 34% [ 30 ].

3.1. Buzz Pollination

Insects, primarily Hymenoptera [ 31 ], use vibrations to extract pollen from a wide variety of flower morphologies with poricidal anthers, that is, anthers where the pollen exits the anther through an apical pore or slit. This phenomenon is known as buzz pollination. In poricidal anthers, the pollen is not freely accessible, and its removal requires vibration. As many as 8–10% of angiosperms possess poricidal anthers that are pollinated through the use of vibrations. Interestingly, buzz pollination seems to have arisen independently several times in about 65 plant families [ 32 ]. Buzz pollination is not limited to a specific flower morphology, although it seems that the Solanum type flower has evolved specifically in response to sonicating bees. Flowers with poricidal anthers are visited by many insects, even non-sonicating insects that chew through the anthers to reach the pollen, but the primary visitors are sonicating bees [ 31 ].

Sonication seems to have arisen in a common ancestor of bees during the early Cretaceous [ 32 ]. A bee lands on a flower and curls with the ventral side of the body around the anthers in a C shape, with the wings tightly folded back over the abdomen during sonication [ 31 , 33 ]. The bee then rapidly contracts the thoracic muscles while preventing the wings from beating. The vibrations are transmitted to the anthers, which resonate, transmitting energy to the pollen, which is then expelled through the apical aperture [ 31 ]. Centrifugal forces are generated, which eject the pollen [ 34 ].

There are both insect-related and plant-related variables that affect buzz pollination. Vibrations produced by sonicating bees can be characterized by duration, amplitude, and frequency. It was found that the greatest effect on pollen removal from anthers was given by duration and amplitude, while frequency had only a weak effect on pollen removal. Moreover, heavier bees produced buzzes with greater amplitude, ejecting more pollen [ 35 ]. The magnitude of the vibration required to eject pollen from the anthers increased with frequency. The vibration frequency determines the time that a force may act on a particle, and therefore higher frequencies require higher amplitudes [ 34 ].

In terms of duration, bees increased the duration of their buzzing when visiting virgin flowers, and buzzes were shorter when returning to flowers that had already been visited. This could suggest that bees adjust the duration of their buzzing in relation to the pollen content of the flower [ 31 ]. In theory, if a bee vibrated for a long enough time, it could extract all of the available pollen [ 34 ].

The frequency of the buzzing is under physical and physiological control rather than behavioral control. This is because the vibrations depend on the muscles of the bee, and therefore there are limits to the frequencies they can achieve. The peak frequency, which refers to the frequency with the greatest relative energy within a buzzing vibration, varies between 100–400 Hz depending on the species of bee. Through harmonic frequencies, which are positive integer multiples of the original peak frequency (sound-standing waves), frequencies as high as 2000 Hz can be reached [ 31 ], but as stated before, this has very little effect on pollen removal. The optimal peak frequencies do, however, vary among plant species but still remain under 1000 Hz.

Plant traits also affect buzz pollination. Plant structures can either enhance or dampen the amplitude of the vibrations. For example, rigid, multi-layered anthers release more pollen compared with flexible anthers when vibrated. It’s reasonable to think that the size of the apical pore influences the amount of pollen released [ 31 ].

3.2. Sweetened Nectar

Yet another example in the realm of pollination is the production of sweeter nectar within as little as three minutes following the perception of sound by flowers of Oenothera drummondii . The flowers of O. drummondii mechanically vibrated in response to recordings of bees and moths flying and also vibrated in response to the flight of a live bee, showing the same increase in nectar sugar content [ 36 ]. The volume of nectar remained the same, meaning that an increase in sugar concentration was not a result of a drop in water content. The velocities of the oscillations of the flowers that in this experiment caused an increase in sugar concentration in the nectar was found in other experiments to be able to elicit defense responses by plants [ 36 ]. Interestingly, the vibration of the flowers depended on the presence of petals, as flowers that had their petals removed or flowers covered by glass ceased to show a response to the sound vibrations.

3.3. Interpreting Relevant and Irrelevant Sounds

These examples show the important ecological role that sound can play in a plant’s life. Plants don’t live isolated from the rest of the world. Instead, there are extensive connections with other plants, animals, and microbes. Around plants, there are rich communities of arthropods, many of which use vibrations to find mates or prey. For example, vibrations caused by the chewing of Plathypena scabra worms caused predatory Podisus maculiventris stinkbugs to begin their search [ 37 ]. Chewing herbivores produce specific high-amplitude vibrations that travel quickly to other parts of the plant, and this can produce a local and systemic response in other parts of the plant. Arabidopsis thaliana leaves exposed to recordings of caterpillars chewing were proved to be primed for defense [ 38 ]. The plants that had been exposed to chewing vibrations showed higher levels of glucosinolates and anthocyanins following herbivory, while there was no increase in anthocyanins in the plants that either received no vibrations or received vibrations from recordings of leafhopper singing or recordings of the wind [ 38 ]. Interestingly, as with the greater amplitude of bee buzzing increasing pollen removal, higher amplitudes induced higher amounts of aliphatic glucosinolates [ 38 ]. It is still to be understood how the response caused by the vibrations of a herbivore can generate an induced resistance or a systemic resistance (for an in-depth study, see [ 38 ]). One possibility is that the plant subject to herbivory integrates the vibrational signal with others coming from the herbivore’s attack. As plants perceive warning signals via VOCs from nearby stressed plants, and VOCs can serve as a sort of chemical language in the communication between plants [ 39 ], also vibrations can be used at least in some cases in plant communication [ 24 , 40 , 41 ]. This is yet another example of the ecological role that sound can play in a plant’s life. The fact that plants perceive sound from so many different sources and adapt proves them to be ingenuously aware of their environment.

4. Sound below Ground

Sound travels easily and far in dense substrates, and soil is a wonderful example. Since the epigeal part of plants does respond to sound, it might be strange that the roots of plants would not be able to do the same, especially considering that vibrations in the soil are present at all times and places. A possible example of the hypogeal part of plants responding to sound vibrations could be the frequency selective behavioral response of Zea mays roots. When exposed to a continuous sound, the root tips very clearly bend towards the source of the sound [ 42 ]. Furthermore, the root tips very clearly show different responses to different frequencies, with the biggest response elicited by a continuous sound of frequency between 200–300 Hz. Interestingly, the root tips generated acoustic emissions, which could be measured at some distance in the hydroponic medium in which the roots were growing [ 42 ].

Pisum sativum roots showed a behavioral response to sound. Even in the absence of moisture, the roots of P. sativum were able to locate water thanks to the vibrations induced by the movement of the water [ 6 ]. Interestingly, in the presence of moisture, the authors showed that the roots preferred the moisture over the acoustic emissions, suggesting that plants could use the sound of water flowing to locate water and then more accurately find the water using moisture gradients. Interestingly, the roots showed avoidance behavior when in the presence of sound equipment, even when the sound equipment was broadcasting the sound of water flowing. The authors hypothesized that the roots were able to sense a cue, such as magnets in the speakers, that directed their growth away from the sound equipment [ 6 ].

5. Can We Communicate with Plants by Means of Sound

Very clearly, sound has a very important ecological role in the lives of plants, but sound vibration treatment can also be used commercially. For example, treatment of harvested tomatoes with sound was shown to delay ripening. Mature green tomatoes were treated with sound waves of 250, 500, 800, 1000, and 1500 Hz for 6 h. All of the sound treatments except the 800 Hz and the 1.5 kHz delayed tomato ripening, with the 1 kHz treatment having the biggest effect. Seven days after treatment with the 1 kHz sound wave, 85% of the treated tomatoes were still green, whereas over 50% of the non-treated tomatoes had turned red [ 43 ].

The treatment with sound waves was shown to decrease both ethylene production in the treated tomatoes and the respiration rate. By the time the respiration rate of the non-treated tomatoes had begun falling after the completion of the ripening process, the respiration rate in the treated tomatoes was still increasing, suggesting that ripening was indeed delayed. Furthermore, the change in color from green to red was more gradual in treated tomatoes compared with non-treated tomatoes. Finally, the flesh firmness of treated tomatoes decreased more gradually, whereas the flesh firmness of the non-treated tomatoes dropped sharply after five days [ 43 ]. This last result could possibly be explained with the help of a previous study which found that treatment with sound waves decreased the deformability of plant cell membranes and made them more rigid. The sound waves seemed to have an effect not on the cell membranes themselves but seemed to cause microfilaments to rearrange and become more rigid. Interestingly, different frequencies had different effects on the deformability of the cell membranes, with higher frequencies causing the deformability to decrease [ 44 ]. The possibility of delaying ripening through sound wave treatment has important ramifications for lengthening the shelf life of products such as tomatoes.

Treatment with sound can also act as a plant growth stimulant, although the underlying mechanisms for this increase in growth have not yet been properly identified. A possible explanation for this is the fact that sound treatment alters plant growth regulatory hormone levels. Sound treatment increases IAA and decreases ABA levels, and this could be a factor in promoting plant growth [ 10 ]. It was found, for example, that following treatment of Chrysanthemum cells with 1000 Hz, 100 dB sound soluble protein content increased significantly compared with a control group. The treatment lasted for 60 min each day, and the treated plants were separated into groups treated for 3, 6, 9, 12, and 15 days. A rich content of soluble proteins is the basis for many physiological activities. Interestingly, soluble protein content increased significantly after six days and even more significantly after nine days but actually dropped back down when the treatment carried on too long, such as the 12- and 15-day treatments. Furthermore, sugar content increased following stimulation compared with the control group. Finally, amylase activity increased following stimulation compared with the control group. The importance of frequency in the response of plants to sound is shown time and time again. While 1000 Hz sound was shown to be beneficial by increasing soluble protein and sugar content and increasing amylase activity, 2000 Hz sound actually proved to be damaging for plant cells [ 19 ].

Other examples of sound treatment as a growth stimulant could be the increased yields in sound-treated tomato or the treatment of wheat with sound waves of 92 dB and 5 kHz to increase yield and dry weight. Photosynthesis was shown to increase following sound treatment in rice and strawberries, and photosynthesis-related proteins were highly expressed following 8-h sound treatments at 250 or 500 Hz in Arabidopsis thaliana [ 10 ]. Sound increased the resistance of strawberries to insects and disease [ 23 ]. SV treatment brought about an increase in the length, number, and activity of Actinidia chinensis roots. Highly dormant seeds of Echinacea Angustifolia showed enhanced germination following treatment with sound vibrations of 1000 Hz and 100 dB [ 23 ]. SV treatment has possible applications in biotechnology, ultrasound being able to enhance Agrobacterium-mediated transformation of several plant species, or audible SVs showing to increase in vitro growth of many plant species [ 45 , 46 , 47 , 48 , 49 , 50 ].

Sound treatment was also shown to induce drought tolerance in Arabidopsis thaliana , leading to a significant increase in survival rates compared with control plants [ 51 ]. At the end of the treatment, plants were sampled to determine changes in transcription. Eighty-nine genes were found to have had their expression altered, 87 of which upregulated, the remaining two downregulated. Of the 87 upregulated genes, 44 are involved in stress-related responses [ 51 ].

The Case of Cavitation

Considering that plants do respond to sound, could plants themselves actually emit sounds? Going even further, if plants do emit sounds, could other plants, or perhaps the same plant, perceive these acoustic emissions and react to them? As mentioned previously, it was indeed found that corn roots grown hydroponically emitted sounds [ 42 ]. However, prior to this discovery, it was already believed that in conditions of drought, cavitation in xylem vessels could be a source of acoustic emissions [ 9 ]. Cavitation is the mechanical breakage of the continuous water column in a xylem vessel that occurs when the tensile strength of the water column is exceeded. This is accompanied by the build-up of mechanical pressure, which, when released, leads to elastic wave propagation [ 11 ]. In other words, there is an abrupt release of tension in the xylem vessel lumen as the liquid water under negative pressure is replaced by water vapor [ 52 ].

Previously the measurement of acoustic emissions following cavitation was done through actual contact between sensors and the plant itself [ 53 ]. Although still interesting, this method does not take into account whether these emissions could be sensed at a distance. However, plants do emit airborne sounds that can be detected from a distance. Different tomato ( Solanum Lycopersicum ) and tobacco ( Nicotiana tabacum ) plants were placed in an acoustically isolated anechoic box under different treatments and were recorded simultaneously at a distance of 10 cm by two directional microphones in order to eliminate false detections of clicks caused by the electrical equipment. The plants were either cut, placed under drought stress, or were in control conditions. The plants that were under stress or cut emitted significantly more sounds compared with the control plants. For the drought-stressed plants, the mean number of sounds emitted per hour was 35.4 for tomato and 11.0 for tobacco, while for cut plants, the mean number of sounds emitted per hour was 25.2 and 15.2 for tomato and tobacco, respectively. Surprisingly, the control plants not subjected to either drought or cutting emitted less than one sound per hour [ 53 ].

Although the precise values differ slightly for tomato and tobacco, the mean peak frequencies of the emitted sounds, in other words, the frequencies with the maximal energy, were between 49 kHz and 58 kHz. These results not only indicate that the emitted sounds are ultrasonic, that is above 20 kHz and not detectable by the human ear, but also confirm that these emissions are detectable at least at a distance of 10 cm. This means that these emissions could be theoretically detected by other organisms, such as insects or other plants [ 53 ].

What makes this experiment especially interesting is the use of machine learning, which refers to a system’s ability to improve and extend itself by learning new knowledge rather than being programmed with that knowledge [ 54 ], to determine whether it was possible to identify the condition of a plant based on the sounds it emitted. The regularized machine learning classifier, which was also trained to discriminate against the electrical noises made by the recording equipment, was able to correctly identify the condition of the plants based on the sounds they emitted. Not only could it distinguish between the control plants and the treated plants, but it could also distinguish between the cut plants and the drought-stressed plants. This is fascinating because it could mean that the sounds that plants emit when under drought stress could carry information; therefore these sounds could be intercepted by other organisms who could then respond and adapt [ 53 ]. Finally, tomato plants were placed in a greenhouse to simulate more realistic conditions [ 53 ]. The recording equipment was trained to discriminate between tomato sounds and greenhouse sounds. A consistent acoustic pattern was found in that the number of sounds emitted is very low when the plant has been recently irrigated, but the number of emissions drops as the plant becomes dry.

These ultrasound emissions could be detected at a distance of 3 to 5 m. This means that it is possible that these acoustic emissions could be perceived by other organisms. For example, many moths that use tomato and tobacco plants as hosts for their larvae can perceive sounds in the frequencies and intensities that were detected in this experiment. It is possible that the information contained in the acoustic emissions of drought-stressed plants could inform these moths not to lay their eggs on these plants [ 53 ]. The emission of sound by drought-stressed plants has important implications in agriculture, as the detection of these sounds could be used to monitor the water status of crops, and this could, in turn, lead to more efficient and precise irrigation, therefore reducing water usage.

Interestingly, it seems that the acoustic emissions of plants can actually be distinguished between low-dB Ultrasonic Acoustic Emissions (UAE), which are below 27 dB, and high-dB UAE (above 35 dB) associated with cavitation. Most investigations on acoustic emission detection have focused on higher dB ranges under the assumption that low dB sounds cannot be distinguished from background noise. However, it was found that signals in the low dB range seem to have a consistent pattern. UAE remained in the low dB range on sunless days and at night and transitioned abruptly to the high dB range on sunny days. High dB acoustic emissions coincided sharply with decreased sap flow rate in Quercus pubescens [ 52 ].

Typically, low dB acoustic emissions increase in intensity as bark tissue expands with hydration, so at night or while it is raining, the intensity of the low dB emissions increases. During the day, as transpiration occurs, the diameter of the stem shrinks as water is lost, and the intensity of the low dB emissions decreases gradually until there is a very abrupt transition to the high dB emissions that are probably caused by cavitation. The highest low dB acoustic emissions occur before dawn, which is when the least water movement occurs. So low dB acoustic emissions closely follow stem radius changes de-trended for growth. There are different possible origins for the low dB emissions [ 52 ].

One possible source for the low dB sound could be the mechanical noise of the stem shrinking and expanding. Or it could be the respiration and metabolic growth activity of the cambium and ray parenchyma cells. These obviously produce diurnal courses of CO 2 efflux from the stem. If the water content is high enough, then the respiration rate follows the temperature. At low water contents, however, the missing water seems to inhibit biochemical activity, regardless of temperature. In conditions of drought, respiration follows stem water content more closely and is largely independent of temperature. Under such conditions, low dB acoustic emissions and stem water content match respiration. When the turgor pressure in the cambium increases, for example, at night, radial growth occurs; consequently, respiration increases, and low dB acoustic emissions increase [ 52 ].

For a long time, it was thought that sounds generated by plants were always a product of cavitation, but the overabundance of sound emissions by plants makes it highly unlikely that all sounds generated by plants are a product of cavitation, considering the limited number of water-conducting elements. Although it seems clear that cavitation can indeed emit sound, some authors believe that sounds generated from the xylem area are not caused by cavitation but by a stable bubble system capable of transporting water through peristaltic waves. Laschimke and colleagues believe that acoustic emissions are a result of sudden surface rearrangements of groups of wall-adherent microbubbles under positive pressure. These microbubbles, which have also been photographed, are largely stable and do not immediately result in embolism [ 55 ]. Laschimke also found, in Ulmus glabra , that acoustic emissions are incessant during transpiration and re-hydration. Therefore it is very unlikely that all acoustic emissions are a result of cavitation. Acoustic activity is undiminished during the night. This means that acoustic activity is not solely a result of transpiration, although transpiration does modify the type of activity, as stated before. The authors analyzed the waveforms of the acoustic emissions in U. glabra during a testing period of 77 h. By analyzing the waveform, it is possible to better understand the underlying physiological processes that cause the acoustic emission [ 56 ]. It is reasonable to expect that a sound emitted by a cavitation event would have a very rapid fading of the acoustic signal, as the water column is rapidly and violently retracted along the vessel following the disruption. However, very few of the 2200 acoustic emission events had a waveform profile of this type. Instead, most acoustic signals showed great variability in the duration, amplitude, and frequency, which can hardly be explained by the cavitation theory of acoustic emission.

6. Plant Alerts

Communicating drought stress.

At this point, it is clear that not only do plants respond to sound, but also that plants emit a wide variety of acoustic emissions, with varying frequencies, from audible to ultrasound, and varying durations and intensities. However, it is harder to actually pinpoint the source of these emissions, and the theory that acoustic emission was a result of cavitation has been put into question, or at least it has been shown that not all emission is a result of it.

As stated before, sound treatment increased drought tolerance in A. thaliana . The same was shown in Oryza sativa . Different rice plants were treated with single frequencies of 0.25, 0.5, 0.8, 1.0, and 1.5 kHz for 24 h. After this treatment, the plants were placed under drought stress for five days. Sound treatment with frequencies of 0.8 kHz and above increased stomatal conductance, relative water content, and quantum yield of PS II. Furthermore, hydrogen peroxide production was inferior in these plants, and the temperature of the sound-treated plants and leaves was inferior compared with control [ 57 ]. So, could it be possible that the acoustic emissions by plants could be perceived by other plants? It has already been mentioned that certain moths can detect sound in the frequencies emitted by drought-stressed tomato and tobacco plants and possibly avoid laying their eggs on those stressed plants; a machine learning tool could very clearly distinguish between stressed and control plants. Could a drought-stressed plant emitting cavitation sounds, among other sounds, alert other plants of impending drought stress? This is a possibility.

Freeze-thaw cycles are the second most important reason for inducing cavitation, so it was natural for studies to focus on the acoustic emission of plants following such cycles. A study found that ultrasonic acoustic emissions are detected during the freezing part of the cycle in conifers, occurring during the ice formation part of the cycle, and most UAE are perceived during the first freeze-thaw cycle, with lower emissions during subsequent cycles. It was also found that samples with water contents close to dehydration emitted UAE during temperature cycles, whereas very dehydrated samples or saturated samples showed few UAE [ 58 ].

But why should plants communicate through the use of sound? What possible advantages could be obtained through the use of sound, as opposed to the use, for example, of VOCs? Firstly, physical signals such as sound can propagate very rapidly, as opposed to VOCs that need to diffuse through the air. Moreover, sounds can be analyzed quickly and can be sensed at very low intensities and over long distances. Sound not only propagates a lot faster than volatiles, but it also has the added benefit of allowing for more accurate source localization. This means that sound has features that degrade predictably over distance, allowing a receiver to estimate the distance from the emitter. Not only that, but acoustic emission is also the result of a physical process, at least in the case of cavitation, which means that there is little to no energy cost involved [ 24 ]. VOCs, on the other hand, represents a significant loss of energy, and a substantial amount of the carbon fixed by plants is re-emitted into the atmosphere through VOC communication [ 59 ]. A possible advantage of VOCs, however, could be their ability to linger in their environment after emission, whereas acoustic signals very obviously dissipate extremely quickly. However, it’s also important to note that volatile signals depend on diffusion and wind direction and, therefore, also suffer from their dilution. This means that although VOCs can linger, they nevertheless need to be present in sufficient quantities to be able to be perceived. Sound, on the other hand, can be perceived by organisms even at very low intensities [ 24 ].

7. Conclusions

At this point, it should be clear that plants respond and emit sound in a wide variety of intensities, frequencies, and durations, as a result of different mechanisms. This is unsurprising in a way, considering the age of plants on Earth and the omnipresent distribution of sound. More study on the acoustic emission of plants is needed to properly understand just what causes sound in plants and how many possible sources of sound there are. A better understanding of sound emission could also clarify other mechanisms, such as cavitation following freeze-thaw cycles and, in general, what happens inside a plant during stress in a non-invasive and real-time manner.

A common theme in studies focusing on the role of sound in plants is the scarce knowledge of the molecular and cellular mechanisms of sound perception and signal transduction. More research at this level of the plant system could determine just how plants react and produce sound, and this could help clarify the ecological role of sound communication in plants. After all, specialized receptors or proteins involved solely in sound perception have yet to be identified in plants. Further research can also clarify the differences and similarities, if they exist, between sound and mechanical stimulation. After that, considering the similarities in essence, the propagation, and in the effects between touch and sound, could light mechanical stimulation cause the same reactions as sound treatment?

Studies on sound perception in plants need to continue also because they have important implications in agriculture and biotechnology. Being able to accurately assess the water status of crops through their acoustic emissions can lead to more efficient irrigation, for example. Sound can also be used to increase the shelf life of products, increase yields, or to trigger plant defenses against pathogens. However, if sound treatment of plants begins widespread use, it is also important to consider its potential side effects on animals, humans, and plants. After all, realizing that plants respond to sound means also accepting that noise pollution affects the plant world as well. Sound treatment on plants needs to be wary of increasing noise pollution problems.

Plants have long been considered to be unchanging, passive, and static organisms, but this view needs to change. Plants are far more ingenious and aware than initially thought, and changing the way we view plants can lead to research that can better take into consideration their capabilities.

Funding Statement

This research received no external funding.

Author Contributions

Conceptualization, L.A.; writing—original draft preparation, F.D.S.; writing—review and editing, V.M.; supervision, L.A. and L.F. All authors have read and agreed to the published version of the manuscript.

Data Availability Statement

Conflicts of interest.

The authors declare no conflict of interest.

Publisher’s Note: MDPI stays neutral with regard to jurisdictional claims in published maps and institutional affiliations.

A great addition to your living space, and one of the best air purifiers.

Aerify plants, air purifying plants, natural air purifiers, crispy wave, japanese asplenium fern.

Aug 24, 2020

Does Music Improve Plants Growth?

Have you ever heard someone say that plants love music? If so, you are not alone. The theory that music can impact plant growth has been around for some time. The idea behind this theory is that plant growth can be negatively or positively impacted by music , particularly certain kinds of music. But is there any truth to this theory? Let's take a closer look at whether or not music can improve the growth of plants.

Can Plants "Hear"?

Plants do not have ears. However, sound is transmitted through waves that first travel through a medium before reaching our eardrums. For instance, sound may travel through the air; when sound travels through air, it causes particles in the air to vibrate. This causes our eardrums to vibrate, which is then converted into sound.

It is entirely possible that plants "hear" music, even though they will not "hear it" in the same way that we hear music. Plants can pick up the vibrations caused by sound waves, which can then impact the plant itself.

It is believed that the vibrations caused by music may stimulate something called "protoplasmic movement", the movement of protoplasm (a matter which composes all animal and plant cells). Stimulated protoplasm can stimulate a plant into growing. With that in mind, let’s continue by looking at what studies specifically have to stay regarding plants and music and how these two may interact.

What Studies Say About Plants and Music

There have been multiple studies regarding the potential impact of music on plants.

One study, conducted in 1962, found that the growth rate of plants can be accelerated when plants are exposed to music. This study found that different types of music, including classical music and raga music, all had an impact on a plant’s growth rate. This particular study found that violin sounds had a stronger effect on plant growth than other types of musical sounds.

Another research held around the same time discovered that music even impacted seeds' development. The study, conducted by a Canadian researcher, found that wheat seeds increased their yield by 66% when exposed to classical music, more specifically, Bach’s violin sonata. These types of studies have been repeated over the years, and they all reached the same general conclusion: that music can impact plant growth.

Plants vs. Different Types of Music

It has been shown through studies that some music can impact plant growth positively. However, do different types of music impact plant growth differently?

In 1973, researcher Dorothy Retallack decided to conduct experiments on different styles of music and their potential impact on plants. In this study, plants were placed near speakers playing various types of musical genres for a several hours period. The study found that plants exposed to classical and jazz music grow towards the sound and even entangled themselves around the speakers . Plants exposed to rock music, however, grew away from the speaker s; they even began growing up a glass wall in the enclosure, suggesting that they were trying to get away from the sound. This strange reaction intrigued the researchers, who repeated the experiment with rock music several times and ultimately concluded that plants exposed to rock music began experiencing damage similar to damage caused by getting too much water.

What about other genres of music? The findings are inconclusive as more studies need to be done on the topic . One thing is sure: d ifferent forms of music have different sound wave frequencies and varying degrees of pressure and vibration. Louder music, like rock, features higher pressure, which some people think might have a detrimental effect on plants.

How Sound Can Be Used to Promote Plant Growth

It has long been theorized that talking to plants can improve plant growth. The reason for this is likely similar to the reason that certain types of music can positively impact plant growth — vibrations from our words can stimulate protoplasm, which in turn encourages plants to grow more quickly and with stronger results.

You would be hard-pressed to find a plant growth book that does not recommend talking to your plants, due to the positive impact it may have. One study has even shown that plants respond more positively to compliments rather than negative comments because compliments and positive words are spoken in a different tone and volume than negative words.

Like talking, music is also being used at professional levels to encourage mature plant growth. For example, it is very common for greenhouses and vineyards to use music to encourage their grape plants to grow more quickly and naturally. Some vineyards even play classical music around the clock to encourage the plants by stimulating stronger growth.

Should I Play Music for My Plants?

If you are a plant lover who is interested in ways to help your plant grow stronger and more quickly, then yes, you can consider playing some music for your plants. It may benefit them by stimulating growth, which will help your indoor plants thrive.

In case you want to try the effect of music on your own plants, you can follow us on Spotify and play our tailor-made soothing playlist.

If you want to know more about this topic, you can consider reading The Sounds of Music And Plants and The Secret Life Of Plants.

Living With Plants

The effects of music of varying types and duration on plants

introduction: (initial observation).

Plants lack the ability to hear sound as humans and most animals do. Plants are relatively simple organisms that use the light energy to conduct a photochemical reaction involving water and carbon dioxide. This chemical reaction known as photosynthesis produces a variety of simple and compound sugars such as starch and cellulose that form the body of the plant.

Plants also lack the ability to comprehend, analyze and think because they don’t have a brain.

Although plants cannot hear and understand music, many (mostly students in different grades) have studied the effects of music on plants. To go one step further, some people talk to their plants and believe that talking will promote growth and health in plants.

Is it possible that sound and music have any affects on plants?

This project guide contains information that you need in order to start your project. If you have any questions or need more support about this project, click on the “ Ask Question ” button on the top of this page to send me a message.

If you are new in doing science project, click on “ How to Start ” in the main page. There you will find helpful links that describe different types of science projects, scientific method, variables, hypothesis, graph, abstract and all other general basics that you need to know.

Project advisor

Information Gathering:

Find out about sound and music. Read books, magazines, search the Internet or ask professionals who might know in order to learn about the effect of sound waves and other wave forms (such as light, Infra Red, Ultra violet, X-Ray) on materials and live organisms. Keep track of where you got your information from.

Following are samples of information that you may find.

Types of Music

Rock – Popular music arising from and incorporating a variety of musical styles.

Country – Popular music based on the folk style of the southern rural United States or on the music of cowboys in the American West.

Folk – Music originating among the common people of a nation or region and spread about or passed down orally, often with considerable variation.

Classical – European music during the latter half of the 18th and the early 19th centuries.

Flamenco – A dance style of the Andalusian Gypsies characterized by forceful, often improvised rhythms.

Jazz – A style of music, native to America, characterized by a strong but flexible rhythmic understructure with solo and ensemble improvisations on basic tunes and chord patterns and, more recently, a highly sophisticated harmonic idiom.

Professor Gordon Shaw is President of the non-profit Music Intelligence Neuronal Development Institute

His brain research uses “music as a window into higher brain function”. Behavioral studies and neurophysiological investigations are done motivated by the structured trion brain model. Results show music enhances spatial-temporal reasoning and learning math, and is of scientific and educational relevance. He has over 165 publications in neuroscience and elementary particle physics including the book -“Keeping Mozart in Mind”. Academic Press 2000. He is co-discoverer of the Mozart effect. His theory work with WA Little in the 1970’s led to the trion model.

Source…

What is The Mozart Effect ®

The Mozart Effect is an inclusive term signifying the transformational powers of music in health, education, and well-being.

The Mozart Effect® represents
The use of music and the arts to improve the health of families and communities
The general use of music to improve memory, awareness, and the integration of learning styles
The innovative and experimental uses of music to improve listening and attention deficit disorders
The therapeutic uses of music for mental and physical disorders and injuries
The collective uses of music for imagery and visualization, to activate creativity, and reduce depression and anxiety

Music-loving plants, music-giving plants

Experiments show that plants thrive if soothing instrumental music is played in the background. On the other hand they shrivel and die if exposed to heavy metal or rock music. And now a Japanese company has created a gadget that puts you in touch with the ‘feelings’ of plants.

Question/ Purpose:

What do you want to find out? Write a statement that describes what you want to do. Use your observations and questions to write the statement.

The purpose of this project is to determine if different types of music affect plant growth.

Identify Variables:

When you think you know what variables may be involved, think about ways to change one at a time. If you change more than one at a time, you will not know what variable is causing your observation. Sometimes variables are linked and work together to cause something. At first, try to choose variables that you think act independently of each other.

Independent variable is music type

Dependent variable is plant growth

Controlled variables are light and temperature.

Constants are the plant type, soil type and the amount of water and nutrients.

Hypothesis:

Based on your gathered information, make an educated guess about what types of things affect the system you are working with. Identifying variables is necessary before you can make a hypothesis.

This is a sample hypothesis:

Plants have no brain and nor hearing organs, so they cannot hear and enjoy music the way that humans do. It seems to me that all others who have performed plant music experiments have been biased and have provided their own perception of music as their experiment results. I hypothesize music has no affect on plants.

This is another a sample hypothesis:

I hypothesize that music can stimulate plant growth by vibrating plant molecules and increasing the rate of photosynthesis reactions. Among rock, classical and jazz music that I am testing, rock will promote the highest rate of plant growth because of the variety of notes used in it.

Experiment Design:

Design an experiment to test each hypothesis. Make a step-by-step list of what you will do to answer each question. This list is called an experimental procedure. For an experiment to give answers you can trust, it must have a “control.” A control is an additional experimental trial or run. It is a separate experiment, done exactly like the others. The only difference is that no experimental variables are changed. A control is a neutral “reference point” for comparison that allows you to see what changing a variable does by comparing it to not changing anything. Dependable controls are sometimes very hard to develop. They can be the hardest part of a project. Without a control you cannot be sure that changing the variable causes your observations. A series of experiments that includes a control is called a “controlled experiment.”

Introduction :

In this experiment you will grow groups of identical young plants in controlled environments and identical conditions while playing a different type of music for each group. To ensure identical conditions (light, temperature, moisture, soil, water, air) you may have access to different rooms and pots with the same conditions or you may construct your own growth chambers.

What is a growth chamber?

A growth chamber is a small cabinet in which light, moisture, temperature and air circulation can be controlled. You can search the Internet for growth chambers in order to get some additional ideas on that.

Sound proof growth chambers for this project may be constructed from large carton boxes, wooden boxes or metal boxes with door.

You may also use empty fish tanks as growth chambers. Glass is relatively sound proof and gives you the choice of using natural light or synthetic light.

The light source can also be fluorescent Strip-Lite fixtures used on aquariums.

IMPORTANT : Only use Strip-Lites over glass tops. They are NOT designed to be safely used over open water.

If you don’t have access to a few empty glass aquariums, you may make your own sound proof boxes in many other ways.

For example you may alter carton boxes and make them sound proof for this purpose.

Styrofoam and sponge can be used to soundproof the boxes.

You will need one sound proof growth box for each plant group and each type and duration of music. You can make a sound proof box by getting a 2′ x 2′ x 2′ carton box and cover inside and outside of the box with some sound proof material. Materials used for a drop ceiling are good for this purpose and you can buy them from hardware stores. Any rubber based foam is also good for sound proofing the boxes. Music suppliers and those who sell material for constructing a music studio carry sound proof foam tiles. Carpet and blanket works as well. The top side of the box can remain open for light to enter, however you will close that too after placing your light source. Your light source can be a fluorescent light. Some opening is required for air circulation.

Procedure overview:

Plant some seeds and wait for germination. You need to have at least 5 plants in each test group.
Dispose of the seeds which do not germinate and transfer those who germinate to small flower pots.
Make one sound insulated growth chamber for each test group. Light source for all boxes must be the same (natural or fluorescent).
Place one group of plants in a growth chamber with no sound source. This will be your control experiment.
Place all other groups of plants in growth chambers with a transistor radio or CD player. Use timers to turn your radio on and off as needed.
Make observations and water all plants daily.
Measure and record the plant growth.

Test groups:

Following are some suggested test groups.

Group of plants with no music
Group of plants with continuous rock music
Group of plants with rock music 3 hours a day
Group of plants with continuous classical music
Group of plants with classical music 3 hours a day
Group of plants with continuous jazz music
Group of plants with jazz music 3 hours a day

The above test groups require seven identical growth chambers. You may restrict your study to less groups if you cannot make seven growth chambers and you don’t have access to seven identical growth environments.

Procedure :

Following is a detail of the procedures:

Step 1: Grow plants from seeds.

Why Grow from Seed?

The most obvious reason for growing plants from seed is the lower cost per plant. Another reason is that many varieties can only be started (or are easier to start) from seed. Finally when you start growing plants from seeds, you will be sure that all your plants are in the same age. It is also a good practice to hand pick seeds that are the same size. (Wash your hands before you start or use tweezers. Bacteria on your hand can grow on seed and void all your experiments)

Soaking the Seeds

Most seeds will benefit from being soaked in warm (even hot but never boiling) water. The addition of a small amount (1/2 teaspoon per pint of water) of saltpeter (sodium nitrate) to the water may help many varieties of seed with very hard seed coats. Soaking for a few hours up to as many as 48 hours in the case of seeds with very hard coats will speed up the germination process. After soaking, blot them a bit with paper towels and plant them in the growing medium immediately or before they have a chance to completely dry out again.

Containers for Germinating Seeds

Any kind of plastic container at least 3 to 3 1/2 inches deep will work. Used containers should be rinsed with a solution of about 1 part bleach to 9 or 10 parts water. Rinse and dry thoroughly before using. I have used the containers that supermarket delicatessens use for salads and pastries, etc. The only problem with them is that holes must be punched at the bottom for drainage. Then some kind of a tray is needed below that to catch the overflow of water. The flats that are designed and manufactured specifically for germinating seeds seems to be the best solution over all. They are available with a variety of pocket inserts for various sizes of plants. It is possible to graduate from the smaller pocket inserts to larger ones as the plant begins to grow. They already have holes at the bottom that allow the excess water to drain into the tray in which they are snugly placed. The drainage of water is very important because soil that is too damp will either cause the seeds to rot or will allow the growth of mold, fungus and other diseases – one of the worst enemies of seeds trying to grow into seedlings. There are clear plastic lids that can be placed over these nursery flats to prevent drafts and to protect seeds from cold drafts. As the plants begin to grow, these lids need to be set off center to allow air flow and finally removed completely to allow the young seedlings adequate air flow. These flats can be reused year after year as long as the 1 part bleach to 9 or 10 parts water solution is used to wash them and then allow them to dry just before reusing.

Growing/Germinating Media

Growing Media, or Germinating Media is plural for Growing Medium or Germinating Medium, This is the material in which the seed is placed to germinate and grow. Of the various growing media, you will need to select the medium that is best for your specific purpose. Listed here are some of the options that are widely available for the gardener.

Peat moss is made up of decomposed aquatic plants and can be very acidic. It retains water and may not allow for adequate aeration or drainage. For this reason it is frequently used with other substances but not by itself.

Sphagnum moss is made up of dried bog material. It is fairly sterile and because it is very lightweight it can absorb as much as twenty times its weight in water. Its value as a fertilizer is not very good, and its ability to absorb water evenly is not very desirable. It, like Peat moss, is a good addition to make up a growing medium but is not the best substance to use by itself.

Vermiculite is expanded mica. It can retain a large volume of water for long periods of time. Although it contains a high level of magnesium and potassium and can hold nutrients and is good for aeration, it is not used by itself but is yet another ingredient in a final mixture for germinating seeds.

Perlite is a volcanic ash. It holds water on its surface but does not allow much absorption. It has no elements needed for plant growth and does not hold nutrients well. It does promote good aeration , stays cool and is a very good ingredient as part of a growing medium.

Sand is a good choice for root cuttings but is a bit too heavy for germinating seeds, it does not hold water, nor nutrients and is not recommended for germinating seeds.

Rich garden soil is good for plants but it does not offer the conditions necessary for germinating seeds because it does not allow for proper aeration and drainage for seeds. It is not sterile but after sterilization (bake it in a pan at 180 degrees for 30 minutes) it can be used as an ingredient in a good growing medium.

Special mixtures prepared for germinating seeds are available at nurseries and garden centers. These are very good for starting your seeds. For a little less money you can prepare your own mixture. A mixture of 1/3 to 1/2 sphagnum or peat moss or any combination of both with 1/2 to 2/3 vermiculite or perlite or any combination of both will make a very good growing medium for germinating most any kind of seed. The ideal mixture would have about 50% solid material, 25% air space (oxygen) and 25% moisture.

It is generally more economical to germinate seeds during the warm months when the heat and light from the sun is free. Temperatures generally in the mid 70s up to 80 degrees F. are needed to germinate most seeds, although there are seeds that require 70 degrees and lower. When temperatures inside drop below 70 degrees at night the germination of many kinds of seeds can be impeded or even halted. It is important to keep the seeds at a constant temperature and away from drafts such as those created by doors and windows. If they are growing near a window to take advantage of the light during the day, it is a good idea to move them farther back as the sun sets to avoid exposing them to drafts. The lack of constant heat is one of the main reasons that seeds fail to germinate.

When germinating seeds indoors during the winter or indoors in air conditioned environments it is important to keep the soil warm. There are several ways to accomplish this. In greenhouses heating coils can be used. For smaller batches of seeds in the typical home it is possible to set the seed flat upon blocks and put a 40 watt light bulb underneath the flat. 60 to 100 watts are likely to generate too much heat. The soil should feel warm, but not too warm. Care should be taken to avoid contact with flammable substances. A heating pad placed beneath the flat or seed containers can be used but care is needed for this too since the controls on some of these heating pads will allow too much heat. Again the soil should feel comfortably warm, not too warm or hot.

Besides warm soil, the air in the room where most kinds of seeds are germinating will need to be at least in the 70s. The higher up you place the seed flats the warmer the air is likely to be in any room. Since heat rises, the top of a refrigerator would be warmer than on a table at waist level. If the room temperature is 70 or 72 degrees f. the difference of 2 or 3 feet of height where the same room may have temperatures from 74 to 78 degrees f. can make the difference in whether or not some kinds of seeds will germinate. Those that require lower temperatures should be placed at lower levels within the room.

Once the seedlings appear and begin growing into plants, the heat should be reduced to around 65 to 70 degrees f. during the day with temperatures as low as 55 to 65 degrees f. at night. There are exceptions to this. Melons, cucumbers, eggplant, peppers, tomatoes, and nearly all tropicals will prefer 70 to 80 degrees f. during the day and 60 to 70 degrees f. during the night.

Light is not the same thing as heat. Although heat is generated by a light source such as the sun or artificial light, it does not continue generating heat when the lights are turned off or when the sun sets. The heat required to begin the germination process should remain constant, day and night, at least during the early stages. The light source may or may not remain constant, but will be necessary for long periods. Simulating the longer daylight hours of spring – 10 to 12 hours per day is best for most species. Those seeds that require constant light will need artificial light (fluorescent or grow lights are best) until germination occurs and possibly for some period of time afterwards. Seeds that require total darkness should be covered with black plastic until germination occurs. Once germination has occurred, all seedlings will need enough light for photosynthesis to enable them to develop into strong healthy plants. If seedlings are growing in overcast conditions of winter, the continued use of artificial lights will be required.

Before sowing seeds in the growing/germinating medium, water it thoroughly and let it drain off. Sow seeds and cover with plastic, glass, or with the specially designed clear plastic covers that can be purchased with the nursery flats. These seeds will probably not need to have anymore water nor mist added until after germination occurs but it is still a good idea to check the top of the growing medium daily to be sure. Too much water (inadequate drainage) will cause seeds to rot, mold, or fungus to grow. Check the growing medium every morning. When the top layer feels a bit dry it can be misted. Watering from the usual containers can disturb the seeds. It is best to sprinkle lightly or better yet, use a spray bottle with a mist attachment. This fine spray will lay down a nice amount of moisture and will not cause gullies or pockets to disturb the seeds. Water is best at room temperature or even a bit warmer – never use hot water nor water that is too cold such as cold water right from the tap. The best time to water is in the morning. Do not allow the growing medium to dry out and do not water so much that is remains soggy or wet. Always water from the top (a mister is best) rather than rely on adequate moisture to soak up from the bottom of the tray. The growing medium needs to be watered from the top down to assure an even distribution of moisture throughout. Too much moisture remaining at the bottom of the tray will cause problems associated with inadequate drainage and the layer at the top may remain too dry.

Fertilizers

The first growth to appear on the seedlings are the cotyledons. These are not true leaves but are food storage cells. This food will only last the seedling a short time and it will be necessary to begin feeding the young plants just as soon as the first true leaves begin to appear, usually within a couple of weeks. Purchase a good quality all purpose water soluble plant food such as Miracle-Gro. Always read the label. When fertilizing young seedlings, start out with a mixture that is about 1/4 the strength that is recommended for mature plants. Use this solution about once a week. Gradually increase the ratio as the plant grows and becomes stronger. After several weeks and after the plant seems strong and healthy, increase the mixture of plant food to water to the full strength as recommended on the label. Do not believe, in the case of plant food or fertilizer, that “more is better”. The manufacturers test their products and know what formula is best. Follow the instructions on the label.

What type of seeds and how many?

You can plant any type of seed that you like. Just consult the seller and make sure that they will germinate fast. If you are not sure, just use beans (any type you like) as seed. Plant 3 seeds in each pot. The reason that you plant 3 in each pot is that some seeds may fail to germinate. You will need at least one germinated seed in each pot. Simply use a pencil to make a 1″ deep hole, place a bean seed in the hole and cover it.

Another method for growing beans is keeping the seeds out of soil or medium until they germinate.

First start the seeds off into growth by chitting them. Chitting overcomes the problem of seeds rotting before they germinate. Chitting, shown in steps 1 to 6 below, is carried out using a plastic food container like those used for sandwiches or the freezer.

Lay a water retentive liner such as a folded paper kitchen towel in the base of the box. Spray the paper towel evenly with water to ensure that it is thoroughly moist all over. Pour away any excess water. Place the bean seeds evenly over the damp towel, about an inch or so apart, to allow for as little root disturbance as possible when the roots grow.

Put the lid on the box. Label the box, most important if your are growing different varieties or other types of seed as well. Place the box in a warm place such as the airing cupboard or a sunny window ledge.

After the first week inspect the seed boxes carefully each day to check on germination. After the seeds have germinated and their roots are an inch long, they can be planted into pots. Fill a 3 and a half inch pot with Potting Compost. Make a generous sized hole in the center of the pot so that the seed can be just laid into it with the root pointing down, but without dibbing the root down into the compost and bruising it in anyway. Fill the surrounding area of the hole with compost to within half an inch from the top of the pot to leave room for watering.

Water the pots to ensure the compost is moist but not saturated. Then place at least 5 pots in each growth chamber that you have prepared in advance.

Check regularly that the pots are not showing signs of drying out, watering when necessary.

Step 2: Experiment the effect of music

Before starting this step, you should have your growth chambers ready and you should have enough same size young plants to place at least 5 plants in each chamber.

All boxes (growth chambers) must be as sound proof as possible. Label each box with your test group as follows:

No music (control)
Continuous rock music
Rock music 3 hours a day
Continuous classical music
Classical music 3 hours a day
Continuous jazz music
Jazz music 3 hours a day

Place radios or CD players in all boxes other than the control. If you are using a radio, you must identify and tune your radio to a station that continuously play the type of music that is needed for that box. If you you are using CD player, have CDs with the type of music that you are testing. For the boxes that must play only 3 hours a day, you may turn the device on and off yourself or you may use a timer that is available in most hardware stores.

Since the boxes are sound proof, you can increase the volume and not much sound will leak out.

Place at least 5 young plants in each chamber. Place the lights and secure them on the top of the box. Cover the box so no sound will leak. (You can ignore small sound leaks). Start the music for all test groups except the control group.

Open the boxes every day and water the plants with a measuring cup or graduated cylinder. Make sure all plants get the same amount of water and nutrients. Make daily observations and record your results and then close the boxes.

After 3 weeks make your final observations. Since you started from seedlings and young plants, any possible effect of sound must be noticeable at this time.

I have not done this experiment myself. Please let me know about your results.

Project Advisor

Materials and Equipment:

Description

Results of Experiment (Observation):

Experiments are often done in series. A series of experiments can be done by changing one variable a different amount each time. A series of experiments is made up of separate experimental “runs.” During each run you make a measurement of how much the variable affected the system under study. For each run, a different amount of change in the variable is used. This produces a different amount of response in the system. You measure this response, or record data, in a table for this purpose. This is considered “raw data” since it has not been processed or interpreted yet. When raw data gets processed mathematically, for example, it becomes results.

This is a sample results table just based on the plant’s height.

You may also use your results table to make a bar graph with one vertical bar for each test group. The height of bar will represent the plant height.

In addition to the plant height, other plant conditions may also be observed and recorded.

Calculations:

If you do any calculations, write them in this section of your report.

Summary of Results:

Summarize what happened. This can be in the form of a table of processed numerical data, or graphs. It could also be a written statement of what occurred during experiments.

It is from calculations using recorded data that tables and graphs are made. Studying tables and graphs, we can see trends that tell us how different variables cause our observations. Based on these trends, we can draw conclusions about the system under study. These conclusions help us confirm or deny our original hypothesis. Often, mathematical equations can be made from graphs. These equations allow us to predict how a change will affect the system without the need to do additional experiments. Advanced levels of experimental science rely heavily on graphical and mathematical analysis of data. At this level, science becomes even more interesting and powerful.

Conclusion:

Using the trends in your experimental data and your experimental observations, try to answer your original questions. Is your hypothesis correct? Now is the time to pull together what happened, and assess the experiments you did.

Possible Errors:

If you did not observe anything different than what happened with your control, the variable you changed may not affect the system you are investigating. If you did not observe a consistent, reproducible trend in your series of experimental runs there may be experimental errors affecting your results. The first thing to check is how you are making your measurements. Is the measurement method questionable or unreliable? Maybe you are reading a scale incorrectly, or maybe the measuring instrument is working erratically.

If you determine that experimental errors are influencing your results, carefully rethink the design of your experiments. Review each step of the procedure to find sources of potential errors. If possible, have a scientist review the procedure with you. Sometimes the designer of an experiment can miss the obvious.

References:

List your references here. Your references may include this website and other websites that I have provided a link for them. It may also include any book that you may study about plant growth or the effect of sound on plants.

Books about the effect of sound on plants such as The Sound of Music and Plants may be found in your local library or purchased from Amazon.com

It is always important for students, parents and teachers to know a good source for science related equipment and supplies they need for their science activities. Please note that many online stores for science supplies are managed by MiniScience.

Testimonials

" I called School Time and my husband and son came with me for the tour. We felt the magic immediately."

- Robby Robinson

" My husband and son came with me for the tour. We felt the magic immediately."

- Zoe Ranson

Contact Info

Our address, working hours.

Week Days: 07:00-19:00

Saturday: 09:00-15:00

Sunday: Closed

Science Project

Testing a Hypothesis—Plant Growth

Charles Darwin believed that there were hereditary advantages in having two sexes for both the plant and animal kingdoms. Some time after he wrote Origin of Species , he performed an experiment in his garden. He raised two large beds of snapdragons, one from cross-pollinated seeds, the other from self-pollinated seeds. He observed, “To my surprise, the crossed plants when fully grown were plainly taller and more vigorous than the self-fertilized ones.” This led him to another, more time-consuming experiment in which he raised pairs of plants, one of each type, in the same pot and measured the differences in their heights. He had a rather small sample and was not sure that he could safely conclude that the mean of the differences was greater than 0. His data for these plants were used by statistical pioneer R. A. Fisher to illustrate the use of a t -test.

Looking at Darwin’s Data

1. Open Darwin.ftm from the Tutorial Starters folder in the Sample Documents folder. This document contains the data for the experiment described above: 1 attribute, 15 cases.

2. Make a case table, a dot plot, and a summary table similar to those shown here.

We see that most of the measurements are greater than 0, meaning that the cross-pollinated plants grew bigger. But two of the measurements are less than 0. Darwin did not feel justified in tossing out these two values and was faced with a very real statistical question.

Formulating a Hypothesis

Darwin’s theory—that cross-pollination produced bigger plants than self-pollination—predicts that, on average, the difference between the two heights should be greater than 0. On the other hand, it might be that his 15 pairs of plants have a mean difference as great as they do (21-eigths of an inch) merely by chance. You can write out these two hypotheses in Fathom in a text object to be stored with your document.

3. From the shelf, drag a text object into the document.

4. Write the null hypothesis and the alternative hypothesis. At right you can see one way to phrase the hypotheses.

You can choose Edit | Show Text Palette to bring up a full suite of tools for formatting text and creating mathematical expressions.

Deciding on a Test Statistic

At the time of Darwin’s experiment, there was no very good theory for dealing with a small sample from a population whose standard deviation is not known. It was not until some years later that William Gosset, a student of Karl Pearson, developed a statistic and its distribution. Gosset published his result under the pseudonym Student, and the statistic became known as Student’s t . When the null hypothesis is that the mean is 0, the t -statistic is simply, x ̄/( s /√ n ), where x ̄ is the observed mean, s is the sample standard deviation, and n is the number of observations.

Let’s compute this statistic for Darwin’s data using one of Fathom’s built-in statistics objects.

5. Drag a test object from the shelf. An empty test appears.

6. From the pop-up menu, choose Test Mean . As shown at right, the Test Mean test allows us to type in summary statistics. The blue text is editable. This is very useful when you don’t have raw data.

7. Try editing the blue text. You can, for example, enter the summary statistics for Darwin’s data.

Here are some things to notice.

Changing something in one part of the test may affect other parts. For example, editing the AttributeName field in the first line also changes it in the hypothesis line and in the last paragraph.

In the hypothesis line, clicking on the “is not equal to” phrase brings up a pop-up menu from which we can choose one of three options. For Darwin’s experiment, we want the third option because his hypothesis is that the true mean difference is greater than 0 . Notice that making this change alters the phrasing of the last line of the test as well.

In addition to simple editing of numbers, we can also determine their value with a formula. For example, we might want to tie the sample count to a slider named n so that we could investigate the effect of different sample sizes. To show the formula editor, choose Edit | Edit Formula with the text cursor in the number whose value you wish to determine. These computed values display in gray instead of blue. Editing the value itself deletes the formula.

Checking Assumptions

Gosset’s work with the t -statistic relied on an assumption about the population from which measurements would be drawn, namely, that the values in the population are normally distributed. Is this a reasonable assumption for Darwin’s data?

Height measurements of living things, both plants and animals, are usually normally distributed, and so are differences between heights. But we might worry, because the two negative values give a decidedly skewed appearance to the distribution.

Fathom can help us determine qualitatively whether this amount of skew is unusual. We’ll generate measurements randomly from a normal distribution and compare the results with the original data.

8. Make a new attribute in the collection. Call it simHeight for simulated height.

9. Select simHeight and choose Edit | Edit Formula . Enter the formula shown below.

This formula tells Fathom to generate random numbers from a normal distribution whose mean and standard deviation are the same as in our original data. We want to compare the distribution of these simulated heights with the distribution of the original data. We can do that directly in the dot plot that already shows HeightDifferences .

10. Drop simHeight on the plus sign to add it to the horizontal axis. The graph now shows the original data on top and the simulated data on the bottom.

One set of simulated data doesn’t tell the whole story. We need to look at a bunch.

11. Choose Collection | Rerandomize .

Each time you rerandomize, you get a new set of 15 values from a population with the same mean and standard deviation as the original 15 measurements. Three examples are shown below.

A bit of subjectivity is called for here. Does it appear that the original distribution is very unusual, or does it fit in with the simulated distributions?

Testing the Hypothesis

Once we have decided that the assumption of normality is met, we can go on to determine whether the t -statistic for Darwin’s data is large enough to allow us to reject the null hypothesis.

In step 7, we typed the summary values into the test as though we didn’t have the raw data. But we are in the fortunate position of having the raw data, so we can ask Fathom to figure out all the statistics using that data.

12. Drag HeightDifferences from the case table to the top pane of the test where it says “Attribute (numeric): unassigned.”

13. If the hypothesis line does not already say “is greater than,” then select that choice from the pop-up menu.

The last paragraph of the test describes the results. If the null hypothesis were true and the experiment were performed repeatedly, the probability of getting a value for Student’s t this great or greater would be 0.025. This is a pretty low P -value, so we can safely reject the null hypothesis and, with Darwin, pursue the theory that cross-pollination increases a plant’s height compared with self-pollination.

Looking at the t -Distribution

It is helpful to be able to visualize the P -value as an area under a distribution.

14. With the test selected, choose Test | Show Test Statistic Distribution . The curve shows the probability density for the t -statistic with 14 degrees of freedom. The shaded area shows the portion of the area under the curve to the right of the test statistic for Darwin’s data. We’ve set this up as a one-tailed test; we’re only interested in the mean difference being greater than zero. The total area under the curve is 1, so the area of the shaded portion corresponds to the P -value for Darwin’s experiment.

Let’s investigate how the P -value depends on the test mean, which is currently set to 0.

15. Drag a slider from the shelf into the document.

16. Edit the name of the slider from V1 to TestMean .

17. Select the 0 in the statement of the hypothesis in the test. Choose Edit | Edit Formula .

18. In the formula editor, enter the slider name TestMe an and click OK .

Now the value of the null hypothesis mean in the test and the shaded area under the t -distribution change to reflect the new hypothesis.

19. Drag the slider slowly and observe the changes that take place.

For what value of the slider is half the area under the curve shaded? Explain why it should be this particular value.

The illustration below shows something similar to what you probably have. Note that the test has been switched to “nonverbose” (choose Test | Verbose ).

Going Further

Play around with changing the data and observing the effect on the P -value. How much closer to 0 can the experimental mean be (without changing the standard deviation) and still have a P -value greater than 0.05? If you make the standard deviation smaller, what happens to the P -value (and why)?
Make a Test Mean object that tests the mean of simHeight instead of HeightDifferences . Notice that each time you rerandomize, you get a new P -value. Think about what it means when the P -value is greater than 0.05. Would you call this a “false positive” or a “false negative”? By repeatedly rerandomizing, estimate the proportion of the time that the P -value is greater than 0.05. What practical significance would that have in planning an experiment?

COMMENTS

(PDF) Effect of Music on Plants
Music influences the growth of plants and can either promote or restrict the growth of plants (depending on the type of music being played). The present experiment is aimed to study the effect of ...
The Sound of Music & Its Effect on Biological Systems: Project ...
of music on plant growth. It is of evolutionary importance that plants can sense and respond to environmental stimuli such as light, temperature, gravity, and touch (Telewski, 2006). The per-ception of sound by plants would, therefore, also hold evolution-ary benefit. It has been shown that sound, as an external factor,
Music And Plant Growth: Learn The Effects Of Music On Plant Growth
Believe it or not, numerous studies have indicated that playing music for plants really does promote faster, healthier growth. In 1962, an Indian botanist conducted several experiments on music and plant growth. He found that certain plants grew an extra 20 percent in height when exposed to music, with a considerably greater growth in biomass.
music and plant growth
the. growth differences are real or just due to natural variability. No. botanist has. yet found a beneficial effect of music or sound on plant growth that is. reliably repeatable and statistically significant. The idea that plants grew better with certain kinds of music apparently. arose in the best selling book, 'The Secret Life of Plants.'.
The Affect of Music on Plants: A Look at Scientific Studies
One of the earliest research studies about the impact of music on plants. In 1962, the head of the Botany Department at the university, Dr. T. C. Singh, oversaw experiments with the effect of different musical sounds on the growth rate of different plants. The study revealed that balsam plants grew at a faster rate when exposed to music.
The Effect of Different Sound Frequencies on Plant Growth
studying the effects of music, and journal articles on the effects of tone to come up with this experiment. HYPOTHESIS Alternate Higher pitched sound tones will have a positive effect on the growth of Wisconsin Fast plants. Null There will be no significant difference in the growth of Wisconsin Fast Plants that are
PDF Effect of Music on Plants
Keywords: Music, Plants, energy, vibration Music and Plants This study was an attempt to understand the effect of music on plant growth and development. Little work has been done in this field wherein the plants have been subjected to different types of sound and the effects being monitored and analysed. Sound is known to affect the growth of ...
Does Music Affect Plant Growth?
Music and Growth. Research has shown that any sound has the ability to stimulate plant growth. In one study, plants that were exposed to sounds for six hours a day showed more growth than plants in a soundless control group. However, that same research showed that while music helped plants grow, it wasn't more effective than non-musical sounds.
Fact or Myth: Does Music Affect Plant Growth?
Bird and Tompkins cited scientific studies that suggested that not only does music help plants grow, but that they have a level of consciousness and can intelligently respond to people. One of the earliest studies of the effect of music on plants was conducted in 1962 by Dr. T. C. Singh, Head of Botany at Annamalia University.
Symphonies of Growth: Unveiling the Impact of Sound Waves on Plant
The application of sound wave technology to different plant species has revealed that variations in the Hz, sound pressure intensity, treatment duration, and type of setup of the sound source significantly impact the plant performance. A study conducted on cotton plants treated with Plant Acoustic Frequency Technology (PAFT) highlighted improvements across various growth metrics. In particular ...
Music and Plant Growth: Here's What the Science Says
For most plants playing classical or jazz music caused growth to increase, while harsher metal music induced stress. This may be because the vibrations of metal music are too intense for plants and stimulate cells a little too much. We think of this like massaging your plant with a song - they prefer a gentler touch. What Botanists Have to Say.
Does Music Have an Effect on Plant Growth
Nov 30, 2016. —. by. Papiya Dutta. in Science Fair Projects. Though it is still a debatable topic, experiments conducted all over the world indicate that music can affect plant growth. While soothing classical music, Beethoven, Brahms have been seen to help in stimulating growth, certain other music hindered their growth rate.
Different Genres of Music: The Effect on the Growth of Plants
The focused and continuous research of plant growth and music continues to be a possible key factor to revolutionizing and utilizing better and healthier growth of plants, encouraging the study to be a completely safe and rational tackle on botanical improvement. D. Scope and Limitations This investigation was conducted in a period of n months ...
Is There a Role for Sound in Plants?
2.3. Sound like Touch. Sound and touch have similar physical properties, and yet plants cannot only properly distinguish between sound and touch, but they are also able to distinguish between relevant and irrelevant sound. The ability of plants to perceive touch has been well known for a long time.
PDF The effect of classical music on plant growth. To what extent are the
Hypothesis: Classical music will increase the rate of plant growth. Null hypothesis: Classical music will have no effect on the growth of Vinca Vines and pea plants. Independent variable: the time the plants were exposed to classical music in the number of days Dependent variable: plant growth in centimeters
PDF Studies Regarding the Influence of Music on The Wheat Plants Growth
wheat growth. The plants have benefited from natural light. Figure 1. Triticumaestivum seeds planted in peat In order to recognize the pots, they we noted by letters: B was the control group, A was the pot with plants subjected to classical music and C was the pot with plants listening to rock music. The experiment lasted 6 weeks, during which
The Effect of Music on Plant Growth and Pests
It increased the seed germination, growth, yield, and metabolism of plants in the same way as the music increased the milk yield of cows. Different plants like different sounds, as the cricket or insect sounds increased the growth, yield, and nutrition of oyster mushrooms. The cuckoo-insect mixed music of 400 Hz was found to increase the growth ...
Does Music Improve Plants Growth?
There have been multiple studies regarding the potential impact of music on plants. One study, conducted in 1962, found that the growth rate of plants can be accelerated when plants are exposed to music. This study found that different types of music, including classical music and raga music, all had an impact on a plant's growth rate.
The effects of music of varying types and duration on plants
Step 2: Experiment the effect of music. Before starting this step, you should have your growth chambers ready and you should have enough same size young plants to place at least 5 plants in each chamber. All boxes (growth chambers) must be as sound proof as possible. Label each box with your test group as follows:
Does music have any effect on plant growth, if so why and how?
It is definitely an interesting idea, but difficult to test rigorously. Answer 3: There is no evidence to suggest that music has any effect on plant growth. Some people believe that it does in a mystical sense, but it has never been verified scientifically. Moreover, there is no reason, scientifically, to believe that plants should be affected ...
Plant growth: the What, the How, and the Why
Growth is a widely used term in plant science and ecology, but it can have different meanings depending on the context and the spatiotemporal scale of analysis. At the meristem level, growth is associated with the production of cells and initiation of new organs. At the organ or plant scale and over short time periods, growth is often used ...
Does Music Affect Plant Growth? Experts Tune in and Reveal the Truth
Yes! As it turns out, there is a positive connection between music and plant growth. Several studies have reached this conclusion through different experiments. Let's explore! One of the earliest studies on the effects of music on plants was performed by Dr. T.C. Singh from Annamalia University in India.
Testing a Hypothesis—Plant Growth
Formulating a Hypothesis. Darwin's theory—that cross-pollination produced bigger plants than self-pollination—predicts that, on average, the difference between the two heights should be greater than 0. On the other hand, it might be that his 15 pairs of plants have a mean difference as great as they do (21-eigths of an inch) merely by chance.
Accelerated growth increases the somatic epimutation rate in trees
Starting ~150 years ago, alternative thinning strategies were applied to subplots of this experiment, resulting in differential stem growth rates among trees. We show that accelerated growth significantly increased the per-year somatic epimutation rate at CG dinucleotides, and that this effect is accompanied by differences in cell division rates.