It would seem that only those who have ears can hear. However, a number of studies conducted in the twentieth century show that plants also respond to the sounds of music. Today, even CDs with music for pets are sold. So what is this – another move of marketers or quite an effective practice?
What music is useful for plant growth and development?
Of course, plants do not listen to music in the usual sense. There is no cactus who is fond of folk music, or dracena – a fan of hip-hop. Studying the effect of music on plants, scientists come to interesting conclusions – plants respond to sound frequencies and their intensity (beats per minute). In fact each plant loves its own music tempo. But in anyway BPM must be less than 120.
Plant growth depends primarily on sound frequencies. Thus, at waves with a frequency of 6 kHz, plants, listening to music, develop faster, at 7-9 kHz – more slowly, and more than 10 kHz and die completely. It is established that low-frequency sounds have a beneficial effect on plants: the roar of sea waves and thunder, the murmur of rivers, the buzzing of bumblebees. In this regard, the most beneficial effect on the growth and development of plants is classical music, the wave frequency of which is usually 3-5 kHz. But rock is absolutely destructive – 8 kHz. Although it is amusing to note that in a number of studies, many tropical plants have been recognized as “fans” of modern rap.
How music affects plants
So how does it work? According to researchers, the basis of the sound effect on plants is a resonant mechanism that promotes energy accumulation and accelerates metabolism in the plant body. Resonance is a physical phenomenon in which the amplitude of oscillations in any system increases sharply if the frequency of oscillations of an external source of influence approaches the frequency of natural oscillations in the system.
The phenomenon of resonance is closely related to synchronization. Synchronization – a phenomenon in which a mode of oscillation is set, in which the frequencies are equal or multiples of each other. The sound signal is perceived by resonant systems in plant cells and tissues, and the amplitude of these oscillations increases them. Eventually there is an increase in the intensity of processes occurring in the cells and tissues of the plant.
Experiments and research
An interesting experience conducted in the 70’s by American researcher Dorothy Retelleck. For the purity of the experiment, she used special cameras with rigidly set light, humidity and temperature, where she placed 10-day shoots of plants. Three experimental groups of plants were kept in the same conditions, while the first group was not “voiced” by music, the second listened to music for 3 hours daily, the third – for 8 hours daily. As a result, the plants in the second group grew much larger than the plants in the first, control group, but those plants that were forced to listen to music for eight hours a day, died within two weeks of the experiment. So it is important not only the quality of music, but also the duration of its impact.
At the same time, research has shown that plants responded positively to Bach’s music and Indian melodies, the stems reaching for the sound source. But to rock music and continuous drum rhythms, they responded by reducing the size of leaves and roots and all the plants deviated from the sound source.
Many similar experiments have been conducted in different countries. USA, 1979, Dan Carlson developed a method of stimulating plant growth, which he called “Voiced Flower”. It included sounding of plants and seeds (music plus high-frequency signals of 3-8 kHz) and foliar treatment with a solution of gibberellin and trace elements. Following this technique, we managed to get a tomato plant 4.5 meters high, which could count 835 fruits. Triple the papaya crop – 135 large fruits grew on one plant, instead of the usual 30-35. A study of the chemical composition of voiced wheat seedlings showed that they contain 20 times more vitamin A than 5, more than 5 times more vitamins C and B. Dan Carlson organized the production of cassettes with music recording that stimulates plant growth, set up trade them and nutrient solutions on a solid commercial basis.
And recently, students at a Russian university conducted an experiment on modern melodies and their impact on the growth of houseplants. Yuri Vizbor’s bard songs, compositions performed by Mykola Baskov, hits of the 90s and music from Soviet films were used for this purpose. It turned out that with great “pleasure” the plants listen to the music of cinema and the melodies of the bard, to Baskov – are indifferent, and the songs of the 90’s – they are simply depressed.
It is possible to treat such researches and conclusions received on their basis with various share of seriousness. But the fact remains – the movement of the protoplasm of plant cells under the influence of music accelerates.