Listening with Edible Plants in Sonic Art

Posted on 6th August 20249th August 2024 by David Vélez (University of Huddersfield)

DOI: 10.5920/DivP.2024.01

Abstract

This autoethnographic article reflects on artistic practice investigating how edible plants sense sound and the political and philosophical considerations that come into play, underlining the pertinence of this practice in addressing critical social-ecological topics in contemporary sonic art such as biodiversity, listening biases, Otherness and empathy. The article navigates a series of sonic artworks concerning beets and rhubarb, emphasising the philosophical and technological considerations emerging when listening to them and other species.

Keywords

Sonic art, Horticulture, Plants, Bioacoustics, Food acoustics

Why Is It Important to Listen with Plants in Sonic Art?

The sensibility of plants to sound, including ultra- and infrasound, is non-cochlear, and their nervous systems are modular and non-centralized (Souza, Toledo and Saraiva, 2018). Perception of acoustic phenomena in vegetal organisms concerns their transpiration and breathing mechanisms (Collins and Foreman, 2001), helping them nourish from acoustic energy (Appel and Cocroft, 2014), and implementing sound to advance learning and support their growth, nourishment, reproduction and survival (Gagliano, 2018).

To listen ‘with’ plants, the artist must create fruitful conditions for an intersubjective encounter, where the audible and inaudible timbres and rhythms of vegetal organism permeate the process and outputs, just as the cycles of vegetables and fruits govern horticulture and gastronomy. Sharing the listening experience with plants enables sonic artists to(a) advance a biodiverse and socially engaged study of sound; (b) contest the agency of anthropocentrism and anthropomorphism; (c) encourage empathy and identify listening biases; (d) engage with an Otherness that presents dramatic differences; (e) surface the limitations of human senses; (f) reconsider time rhythm in creation.

On Edible Plants

Ecological and sensible horticulture has helped many plant species thrive and survive (Kress and Krupnick, 2022) to the point that, after thousands of years of human-vegetal coevolution, tea, wheat, and other plant species show signs of learning from our alimentary needs to take advantage of our dependency on them and thrive as crops (Jackson, 1996). Audra Mitchell is a researcher on political ecology who invites creative practitioners to focus on the vegetal species we use for consumption after the moral amnesty that our nutritional reliance on them gives us. (Mitchell, 2014) In this regard, listening with edible plants can (a) reveal connectedness between sonic, olfactory and gustatory stimuli; (b) exercise well-being and self-care, inviting artists to establish a vibrant and nourishing relationship with their food, bodies, community, and territory; and (c) emphasise the interdisciplinary scope of sonic art, with potential contributions to horticulture, gastronomy and food anthropology.

What Are the Philosophical Considerations of Listening with Plants?

To address this question, I want to navigate and reflect on fragments from the book Through Vegetable Being, by Luce Irigaray and Michael Marder.

(…) What can listening signify if it does not imply a relation to, and with, a living being here and now present to and with me? To reach such a way of listening, we must first experience what silence is. (Irigaray in Irigaray and Marder, 2016, 95)

Luce Irigaray parallels Hegel’s ideas and Buddha’s teachings to highlight the importance of silence in our sonic encounters with plants. She suggests that, for Hegel, the philosophical aim is to gather all discourses into one wholeness. For Buddha, she observes, the purpose is to reach silence. Irigaray acknowledges that modernity approaches silence with disdain, advancing a culture that favours speaking and rewards selfishness.

Listening to the uniqueness of another existence, and considering its irreducibility with respect to my own (…) is to recognize another life as transcendent to my own and to my world, forever unknowable to myself. (Irigaray in Irigaray and Marder, 2016, 96)

The theories of Luce Irigaray invite us to establish a position of attentiveness and selflessness to create conditions for a potential contact between humans and plants. For her, it requires preserving a buffering silence between the listening subject and the aural environment, where time-space limits are respected. In silence, she acknowledges the possibility to experience our environment in its sonic vitality and vibratile interconnectedness. In Irigaray, the encounter with this vitality ‘(…) contributes to restoring to me my breath, my freedom, and a living presence, in spite of so many codes that had transformed me into a robot.’ (Irigaray and Marder, 2016, 97)

On how to listen to plants, Michael Marder reflects:

Plants by far exceed animals and human beings in their attentiveness to what is going on around them with regard to the levels of light, heat, moisture, movement, vibration… (Marder in Irigaray and Marder, 2016, 268)

Marder presents the concept of non-objectification, which is key to imagining what it means to attend to the sensibility of vegetal life forms.

[Plants’] attention is inseparable from their life and growth. From a magnificent sequoia to a blade of grass, a plant attends to the physical elements, precisely, because the elements are not objects and cannot be objectified. Only then, in such non objectification the elements and life itself are respected in their proper being. (Marder in Irigaray and Marder, 2016, 273)

In his get-together with plants, Marder detects a vegetal sensibility that operates in connection with rootedness. This sensibility, he contends, corresponds to their close relationship with the soil and place in which they are grounded (Irigaray and Marder, 2016). Here, the author perceives one of the most dramatic discrepancies between animal and plant organisms. This uniqueness helps them establish a strong connection with the place they constitute and inhabit. Marder invites us to ponder a model of place that draws from vegetal perception that considers soil nutrients, humidity, and acidity.

I reflect on my experience with plants and infer that we can speculate about the elements they attend by analysing how they inhabit their place. I reflect on how the exchanges with plants transform my perception of time:

After a while I could no longer tell if I spent twenty minutes or two hours with plants. My sense was that everything happened more slowly and that deceleration facilitated a closer attention to plants and to the elements, where living became more vibrant.

Photosynthetic Rhythms

The temporalities of capitalism, particularly night shifts, extended work hours, and extensive commute and travelling, deny the human body the opportunity to harmonise its internal clock with the rotation of the earth around the sun (Birth, 2007). Contemporary technological advancements create continuous production chronograms and schedules that ignore the diverse micro-rhythms intertwining natural cycles. In this regard, cultivating plants effectively synchronises the human body to its organic flux, decreasing the risk of depression and anxiety (Asai et al, 2018), which is also the principle of Care Farming and other therapeutic developments in horticulture and mental health. In vegetal organisms, circadian rhythm provides information that helps them regulate their metabolism and control gas exchange between the plant leaves and the atmosphere via stomata. Considering that vegetal life supplies 98% of the oxygen available, we can imagine the rhythms of plants intertwining with our bodily patterns as part of an ecosystem which breathes synchronously through the organisms that constitute it.

Autoethnography 1: Listening with Beets

Between May of 2021 and 22, I centred my research on the acoustics of beets through two indoor horticultural experiments, which brought forth an installation entitled One Last Perfect Day exhibited in the Modern Art Museum of Medellin (Colombia), and a CD entitled Beta Vulgaris published by experimental music label Sublime Retreat (Vélez, 2022).

I became interested in beets for their distinctive flavour, high nutritional value, and wide range of potential applications, including treatments to slow down the effect of Alzheimer’s in the brain (Ming, 2018) and advances in sustainable solar energy panels (McHale, 2011).

My enquiries on the acoustics of growing beetroot led me to research previous experiments in bioacoustics applied to farming and gardening, where I learned about the regular use of sine waves vibratingat specific frequencies to which plants have responded with improvements in well-being and growth. When acoustic energy gently scrubs the stomata in the dermis, this enhances transpiration and breathing, removing particles blocking the plant pores and improving the intake of carbon dioxide and water (Collins and Foreman, 2001).

Initially, I investigated bioacoustic research incorporating sine tones in beets (Petrescu, Mustăţea and Nicorici, 2017), beans (Harris and Collins, 2001; Pujiwati et al, 2018), thaliana (Kim et al, 2021), okra and zucchini (Creath and Schwartz, 2004), and marigold (Chowdhury and Gupta, 2015). This enabled me to advance a combination of tones to aid the beets in the experiments.

Secondly, I discovered that chewing sounds from insects and worms strengthen the immune system of plants, which is the case with Arabidopsis thaliana and their sensibility toward food-intake sounds made by caterpillars (Appel and Cocroft, 2014). Over millions of years plants have evolved to anticipate the presence of predators by associating the volatile gas emissions of injured conspecifics with the sounds made by their hunters. To articulate this finding in the experiments, I advanced Foley to carefully mimic the sounds of insects and worms chewing to play them later to the beets.

Finally, research by the Royal Horticultural Society and the National Institute of Agricultural Biotechnology in South Korea evidence the beneficial effects of speaking to plants, especially when we do so in an affectionate manner, which led me to ponder speaking to the beetroots to support their development in my investigation (BBC, 2009; Jung et al, 2018).

The first experiment took place in my studio, where I planted beet seeds and began combining performance and composition to advance sequences that I played to them for 4 hours every day. Throughout the experiment, I followed growth charts and got advice from seasoned farmers, proving that the sounds I created had triggered a moderately positive reaction in the plants over the period until harvest. In the artistic process, the fragments made with sine waves stretched through lengthy combinations advancing slowly and subtly, informed by my investigation of bioacoustic testing on farming, but also by numerous hours observing the growth of the beets, which affected my perception of time, due to the patience and deliberateness they demanded. The Foley sounds were sudden, transient and sharp, developing a faster cadence that embodied the rhythms of insects and other species I mimicked. To witness the growth of the curly green leaves, the dispersion of the intense violet venations, the bolstering of the lively violet stems, and the formation of the rounded radiant bulbs was a fascinating experience. It unveiled the material plasticity of the beets, which helped me communicate with them through my sensibility to sound, light and touch, after I fed and bolstered the beets in response to their colour, shape, textures, and robustness. The dedication and time I devoted to them rewarded me with tasty leaves, and bulbs that created a symbiotic circular exchange between the plants and me.

This experiment was recreated later in a salon of the Modern Art Museum in Medellin, which presented challenging lighting conditions that had us using LED lights that worked well with the original sound frequencies. Also, I set up a microphone connected to a transducer that projected the voice of the visitors towards the beet roots, which turned out to be both beneficial to the plants, and emotionally significant to the spectators. Finally, the beets were harvested, cooked and consumed in a workshop led by horticulturist and cook Elena Villamil, who mentioned that their flavour was specially sweet, maybe also a product of the combination of sounds and light frequencies.

Autoethnography 2: Listening with Rhubarbs

Forced Farmed Rhubarbs

In West Yorkshire, it is traditional to grow rhubarb plants in dark shades as part of a process known as ‘forcing’, in which the stems develop with exceptional speed, producing a popping squeaky sound that is as unique as their pink colour and sweet flavour. This practice originated in 1877 when fruit was scarce and coal was available to heat winter crops in sheds during Northern England’s short wintertime days (Slow Food UK, 2022).

On March 10 of 2022, I visited the farm of Robert Thomlinson, who invited me to listen to and record these sounds. A long period of silence preceded the first rhubarb sound, demanding attentiveness, quietness, and patience, which brought forth the subtle sounds of passing vehicles and barking dogs surrounding the plants in this quiet place. Finally, the wait was rewarded with the first popping and squeaky rhubarb sound, leading me to wonder whether it was actually a rhubarb. Perhaps a water leak dripping over a metallic surface, or a loose and stretching piece of wood? Then, the sounds increased their frequency, immersing me in this chorus of plants growing in the dark, that exhibited a joyful, unique and rare beauty.

But what about the rhubarbs sharing the experience with us? Were they aware of their own sounds? What do these sounds imply for them? These questions led me to investigate the nocturnal mechanisms of plants when they are unable to synthesise due to the absence of sunlight. They respond by making arithmetic calculations to administer their energy levels, through the agency of two kinds of molecules called starch and time (Howard and Smith, 2013). I began to appreciate how forced rhubarbs resonate at the frequency of their stretching stems, releasing acoustic energy under high concentrations of chemical energy. As impressive as it is, it is perplexing to realise that farming takes advantage of this process, further forcing vegetables and fruits out of their natural rhythms and surfacing more of the problematic aspects of horticulture.

Listening to the sounds of forced rhubarbs, I had the sense of human and edible plants sharing the imposed and unnatural rhythms of capitalism and modernity. These sounds, unfamiliar to non-forced and wild rhubarbs, point to the intricate relations between plants and us that surface in farming.

The output of this project is an installation entitled Singing in the Dark (Vélez, 2022), presented in a dark art gallery inhabited by rhubarbs and other plants, illuminated with LED lights. Here, the visitors listened to untreated and processed rhubarb recordings projected through a quadraphonic system and other transducers.

Home Grown Rhubarbs

In my house I grow rhubarbs whose stems I cook to make marmalade; and one time I noticed Perionyx Excavatus earthworms emanating from the dirt surface. This annelid species is often cultivated in farms for its ability to feed from decaying roots and leaves, keeping the soil vital in continuous regeneration, while improving the quality of the nutrients absorbed by the plants.

As discussed, chewing sounds from tiny animals can benefit plants, boosting their immunity and showing their superior sensibility to intensities that are imperceptible to human listening and challenging for traditional recording equipment. In order to attend to these sounds, on 2 May 2023, I placed a geophone and a miniature hydrophone inside the soil of the rhubarb after acoustically isolating the pot with cardboard, textiles, foam, and bubble wrap. On the recording, the apparently quiet soil emerged vibrant and active, and the chewing and other earthworm sounds can be heard with surprising clarity. Soil, normally understood as quiet and inanimate, revealed to the microphones its vitality, mediated by its capacity to produce and absorb sonic vibration.

Listening with rhubarbs implied focusing on the sounds that are important to them, presenting the alliances that they establish with other organisms to cooperate and thrive. To understand the significance of soil-transmitted sounds in plant-human cooperation, I reached out to the research of Christian H. Mohr concerning water intake from tree roots under seismic vibration. Mohr suggests that the low acoustic vibration of earthquakes increases the amount of water available for trees when rooted in soils with limited access to hydric sources. In the future, the study of this phenomenon could inform the development of technologies capable of predicting earthquakes, thanks to the privileged sensibility of plants to water and sound (Mohr et al, 2021). To articulate my experience listening and recording rhubarb soil, I wrote:

In the vibratile realm of the plants, the soil, the water and the geological stratums are alive in the same way that the plants are alive. They are alive to the extent they are allies, and only in alliance organisms become themselves. Consequently, one is alive on account of one’s contribution to the coevolution process one attends.

The untreated recordings were presented in an installation involving the presence and scent of soil, exhibited in the festival Sound Plotting 2 in Brighton (UK), and Afectes sònics. Art sonor I expansió de la percepció in La Panera Museum, in Lérida (Spain).

References

Appel, H. and Cocroft, R. (2014). Plants Respond to Leaf Vibrations Caused by Insect Herbivore Chewing. Oecologia 175(4): 1257-1266.

Asai, Y. et al. (2018). Farming Habit, Light Exposure, Physical activity, and Depressive Symptoms.
Journal of Affective Disorders 241, 235-240.

BBC. (2009). Darwin Relative Helps Plants Grow. BBC News Surrey. http://news.bbc.co.uk/1/hi/england/surrey/8113718.stm

Birth, K. (2001). Time and the Biological Consequences of Globalization. Current Anthropology 48(2): 215-236.

Chowdhury, A. R. and Gupta, A. (2015). Effect of Music on Plants: An Overview. International Journal of Integrative Sciences, Innovation and Technology 4(6): 30-34.

Collins, M. and Foreman, J. (2001). The Effect of Sound on the Growth of Plants. Canadian Acoustics 29(2): 3-8.

Creath, K. and Schwartz, G. (2004). Measuring Effects of Music, Noise, and Healing Energy Using a Seed Germination Bioassay. Journal of Alternative and Complementary Medicine 10(1): 113-122.

Gagliano, M. (2018). Inside the Vegetal Mind: On the Cognitive Abilities of Plants. In Frantisek Baluska, F., Gagliano M., and Witzany, G. eds., Memory and Learning in Plants, pp. 215-220. Cham: Springer.

Howard, M. and Smith, A. (2013). Plants Do Sums to Get Through the Night. John Innes Centre https://www.jic.ac.uk/news/plants-do-sums-to-get-through-the-night/

Irigaray, L. and Marder, M. (2016). Through Vegetable Being. Columbia University Press.

Jackson, F. (1996). The Coevolutionary Relationships of Humans and Domesticated Plants. American Journal of Biological Anthropology 101(S23): 161-176.

Jung, J., Kim, S. K., Kim, J. Y., Jeong, M. J. and Ryu, C. M. (2018). Beyond Chemical Triggers: Evidence for Sound-Evoked Physiological Reactions in Plants. Frontiers in Plant Science 9, 25.

Kim, J. Y., Lee, H. J., Kim, J. A. and Jeong, M. J. (2021). Sound Waves Promote Arabidopsis thaliana Root Growth by Regulating Root Phytohormone Content. International Journal of Molecular Sciences 22, 5739.

Kress, W. J. and Krupnick, G. (2022). Lords of the Biosphere: Plant Winners and Losers in the Anthropocene. Plants People Planet 4(4): 350-366.

Ming, J. (2018) Lecture at the 255th National Meeting & Exposition of the American Chemical Society.
https://www.sciencedaily.com/releases/2018/03/180320084414.htm

Mitchell, A. (2014) A Growing Concern. Wordy Website.
https://worldlyir.wordpress.com/2014/01/05/a-growing-concern/

Mohr, C. H., Manga, M., Helle, G., Heinrich, I., Giese, L. and Korup, O. (2021). Trees Talk Tremor—Wood Anatomy and δ13C Content Reveal Contrasting Tree-Growth Responses to Earthquakes. JGR Biogeosciences 126, e2021JG006385.

Petrescu, S., Mustăţea, R. and Nicorici, I. (2017). The Influence of Music on Seed Germination of Beta Vulgaris L. Var. Cicla L. Journal of Young Scientist 5, 67-72.

Pujiwati, I. Guritno, B., Aini, N. and Sakti, S. (2018). Examining Use of Sonic Bloom Technology on the Stomata Opening of Drought-Stressed Soybean. Biosciences Biotechnology Research Asia 15(4): 861-869.

Sandquist, C. and McHale, J. (2011). Improved Efficiency of Betanin-based Dye-sensitized Solar Cells. Journal of Photochemistry and Photobiology A: Chemistry 221(1): 90-97.

Souza, G., Toledo, G., and Saraiva, G. (2018). Toward Systemic View for Plant Learning: Ecophysiological Perspective. In Frantisek Baluska, F., Gagliano M., and Witzany, G. eds., Memory and Learning in Plants, pp. 163-190. Springer.

Slow Food UK. (2024). Yorkshire Forced Rhubarb. Slow Food in the UK. https://www.slowfood.org.uk/ark-product/yorkshire-forced-rhubarb/

Vélez, D. (2022) Beta Vulgaris [Album]. Sublime Retreat.
https://sublimeretreat.bandcamp.com/album/beta-vulgaris

Vélez, D. (2022) Singing in the Dark.
https://davidvelez.bandcamp.com/album/singing-in-the-dark-the-sounds-of-forced-rhubarb

About the author

David Vélez is a sonic artist investigating the acoustics of food and horticulture, emphasising the sensibility of edible plants and their ecosystems to sound. His work is interdisciplinary, implementing technologies from bioacoustics, geoacoustics, ethnography and food anthropology to advance politically engaged projects. He centres his work on musical synthesis, electroacoustic transduction and field recording, focusing on underground and subaquatic sounds.