Can Ultrasound Accelerate Plant Growth?

By Tj Byers
Published on May 1, 1984
1 / 4

Fig. 1: The hearing capabilities of several different mammals are compared to the frequency range effective for plant stimulation. Higher frequencies seem to stimulate greater growth.
Fig. 1: The hearing capabilities of several different mammals are compared to the frequency range effective for plant stimulation. Higher frequencies seem to stimulate greater growth.
2 / 4

List of materials for building an ultrasound generator.
List of materials for building an ultrasound generator.
3 / 4

Fig. 2: The results of one experiment showed a dramatic increase in growth rate with ultrasound stimulation.
Fig. 2: The results of one experiment showed a dramatic increase in growth rate with ultrasound stimulation.
4 / 4

Fig. 3: The wiring diagram should help you to build a simple and inexpensive ultrasound generator.
Fig. 3: The wiring diagram should help you to build a simple and inexpensive ultrasound generator.

In an effort to keep you informed about the latest developments in the scientific and electronic worlds, I regularly devote time to reporting current (as well as, occasionally, forgotten) technology. Two issues ago–in How a Solar Root Stimulator Can Help Grow Healthy Plants–I discussed some experiments in which photovoltaic cells were used to stimulate the roots of plants, resulting in a significant increase in the rate of plant growth.

And, as it happens, I recently found yet another intriguing report… one which claims that plant growth can be speeded up by subjecting the greenery to ultrasound. “Now this,” I thought, “is a new twist.”

Ultrasonics 

Judging by your overwhelming response to the article on photovoltaic root stimulation, I’m sure that many of you will be anxious to give this new technique a try. Once again, though, let’s start by discussing the principles behind this exciting development.

Sound is vibration that travels through air. Without those molecules of nitrogen, oxygen, carbon dioxide, etc., there would be no sound: A telephone ringing in outer space would go unanswered even if an astronaut happened to be floating by, because no one could hear it. Sound vibrations come in a wide range of frequencies. The audio range–which extends up to about 20,000 vibrations per second (cycles per second or CPS)–includes those frequencies that people can hear. Of course, some individuals do hear better than others. Women, in particular, can usually detect noises that are of too high a frequency for men to hear. And most animals exhibit hearing capabilities superior to those of humans. Many insects, for example, can produce and hear frequencies that are beyond our limitations.

When the frequency of a sound extends beyond our normal hearing limit, we have ultrasound. Fig. 1 illustrates the sound frequency range from 0 to 50,000 CPS and shows the hearing capabilities of humans and several animals.

Comments (0) Join others in the discussion!
    Online Store Logo
    Need Help? Call 1-800-234-3368