Tomato Plants In or Out...Ask Them- Plants Emit Sounds Too High For Human Ears When Stressed Out

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Some plants emit “ultrasonic clicks” inaudible to the human ear when under life-threatening stress, a new study has found. Recordings reveal each sound contains information about a plant’s current state of being.

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Previous studies have found that stress caused by changes in temperatures and light, as well as “herbivore attack,” can alter a plant’s phenotype, resulting in changes in color, smell, and shape. Stressed plants have also been found to give off volatile organic compounds. To examine whether plants make audible sounds as well, researchers at Tel Aviv University recorded tomato and tobacco plants that were deprived of water, having their stems cut, or were otherwise comfortable. Microphones focused on an ultrasonic sound range between 20 and 150 kHz.


Stressed plants were found to emit significantly more sounds than plants from the comfortable control group. Not only were they noisier, but the researchers claim that they gave off different sounds depending on what was happening; sounds that carried information about the physiological state of the plant. A specially designed machine learning model was reportedly capable of distinguishing between plant sounds and general background noise, going so far as to identify whether a plant was water-deprived or being cut.