You may remember that many years ago before Charles became king, he spoke about talking to plants. At the time he had a reputation for being a bit out of step with reality but he was right. He was ahead of the game. And it’s been proven to a certain extent with a recent study which tells us that stressed-out plants make sounds if they are thirsty or have been ‘injured’ (damaged).
The plants are quiet when they are not stressed or damaged. It appears that they are vocalising their stress. But the big question is whether they are communicating to other plants or even animals such as bees. That is the next stage of research.
But it is remarkable to note that they do create sounds when stressed. It is perhaps one more stage in progress in understanding plants better as humans are now learning to understand animals, their sentience and their intelligence.
In fact, in January 2022, said David Attenborough remarked in a BBC television series that, “We don’t engage with plants enough.” Prince Charles, as he then was, believed that speaking to plants helped them to grow.
Current research has discovered that plants emit noises that can travel through the air and be detected about a metre away particularly when they are experiencing stress.
The sounds resemble popping bubble wrap and they are ultrasonic. This means that they are too high-pitched for humans to hear. The scientists lowered the frequency so that they can be heard by people.
It was known that plants could produce ultrasonic vibrations. However, this is the first time that these vibrations had been found to travel through the air.
The researchers believe that it is possible that insects and other animals might be able to detect the sounds. If that is the case, it is conceivable that insects for example experience a cacophony of sound when they collect pollen. Perhaps the plants are talking to them and even guiding them!
The research was carried out by Israeli scientists. They studied tomato and tobacco plants. They subjected them to stress both in terms of not watering them and cutting them. They used microphones to record both healthy and stress to plants in a soundproof acoustic chamber.
They analysed the information using AI computers.
Lilach Hadany said:
When tomatoes are not stressed at all, they are very quiet [but] we found that many plants-corn, wheat, grape, and cactus plants, for example, emit sounds when they are stressed.
They don’t know how the sounds are created but they believe it might come from the formation and popping of air bubbles within the plant’s vascular system. This process is called “cavitation”.
There are not sure whether these sounds are a form of communication. It may be possible that other plants pick up the sounds so it might indeed be a form of communication.
Now that we know that plants do emit sounds, the next question is who might be listening? We are currently investigating the responses of other organisms, both animals and plants, to the sounds.