Leisha Plant & Kitchen Alchemy · Evening reading, Day 3 of 7
One of seven evening readings from Plant & Kitchen Alchemy, a Living Ground workshop on soil, plants, microbes and food as medicine. Each piece stands on its own; you can also start from the beginning.
This morning a group of people sat alone in a garden, each one in front of a single plant, for twenty minutes, without speaking. It was not quiet in there.
In 2023 a team at Tel Aviv University placed tomato plants inside soundproof boxes with ultrasonic microphones pointed at them. They stopped watering some and cut the stems of others. The plants clicked. A thirsty tomato produced around thirty-five clicks an hour, in bursts, each one roughly as loud as ordinary conversation, pitched far above anything a human ear can reach. Well-watered, uncut plants stayed almost silent. Tobacco clicked too, and so did wheat, corn, Cabernet Sauvignon grapevines and a pincushion cactus. A machine-learning model trained on the recordings could tell a thirsty tomato from a watered one, and a tomato from a tobacco plant, even in a noisy greenhouse.
What makes the sound is worth sitting with. Inside a stem, water climbs in unbroken threads under enormous tension. As a plant runs dry, that tension rises until a thread snaps and air rushes into the gap. The column breaks, and the break has a voice. Every click is the sound of a plant working at the edge of what it can hold together.
Lilach Hadany, who led the work, chooses her words precisely: they have shown that plants emit informative sounds. Stay on that word for a moment. Informative. There is information moving through the air of every garden, every orchard and every field on earth, and it has been there the entire time.
And something is listening. In 2025 the same university reported that female Egyptian cotton leafworm moths avoid plants that are making dehydration clicks, and go elsewhere to lay their eggs. Where a moth lays is the most consequential decision she ever makes, and she appears to make it partly by ear. It is the first evidence of an animal choosing on the strength of a sound a plant is producing: a mother listening to a nursery to find out whether it is thirsty.
Then there is the finding I keep coming back to, because it is about taste. In 2019 a team studying the beach evening primrose (Oenothera drummondii) ran the question in reverse. Rather than listening to the plant, they played something to it: a recording of a bee’s wingbeat. Within three minutes the flower had raised the sugar concentration of its nectar from twelve or seventeen per cent to around twenty. Silence did nothing. High frequencies did nothing. Only the low pitch of a flying pollinator, roughly 0.2 to 0.5 kilohertz, produced the change.
And the ear turned out to be the flower itself. The bowl of petals catches the sound and vibrates with it, the way a dish catches rain. Remove some of the petals and the plant stops responding. It goes deaf. Sit with that for a second. A flower hears a bee approaching and makes itself sweeter before the bee arrives. Not over a season, not over a day, but in the time it takes to boil a kettle.
We speak about taste as though it were a fixed property, the way a stone has a weight. Here is a plant adjusting its own flavour, in minutes, in answer to something it heard coming. Sweetness as a reply.
None of this is mysticism. It is microphones, control groups, removed petals, silent trials and peer review. The humbling part is not that the garden turns out to be secretly magical. It is that the garden has been doing this for the whole of our history with it. Ten thousand years of leaning over these plants, pulling them up and eating them, and we only built the instruments to notice in the last decade. Our hearing gives out somewhere around twenty kilohertz. The clicks live above it. We were standing right there.
So what else? Our eyes receive a sliver of the light that falls on us every day. Birds see colours we have no words for. Bees read patterns on petals that are, to us, blank. A dog walks down a street reading yesterday afternoon off the pavement. Each of those was once a thing nobody knew was there to be missed.
That is the thrilling part, and it is bigger than any single study. Not the questions we know we cannot answer yet, though there are plenty of those and they are wonderful. The ones that stop me are the questions nobody has thought to ask, because we have no sense that would have raised them. Before 2023 nobody was failing to hear the tomatoes. Nobody knew there was anything to hear.
A garden is not a quiet place that we have understood. It is a loud, crowded, talkative place, almost all of it pitched outside us, and we are only beginning to build ears for it. Go and sit in one. Whatever you notice, there is more.
Sources
- Stressed plants make ultrasonic clicking noises (on Khait et al., Cell, 2023)
- Flowers can hear bees and make their nectar sweeter (on Veits et al., Ecology Letters, 2019)
- First evidence of insects choosing an egg-laying site based on plant sounds (on the 2025 moth study, eLife, Tel Aviv University)
