In 2019, studies revealed that plants are sensitive to sound, particularly music, and that this can influence their growth. 

According to research by a Tel Aviv university, plants emit sounds at a frequency that humans cannot hear when they are stressed by a lack of water or when their stems are cut.

The scientists placed microphones 10 centimetres from tomato and tobacco plants. They then picked up sounds coming from the plants, in an ultrasonic range of 20 to 100 kilohertz. Some insects may be able to hear these ultrasounds from up to 5 metres away. A butterfly might decide not to lay its eggs on a plant if it finds it stressed by a lack of water. Plants could even hear that other plants are lacking water and react accordingly. 

Researchers are developing a procedure for learning to differentiate between the different sounds made by plants. The study only concerns tomato and tobacco plants, but the scientists are convinced that other plants can also make sounds.