Talk to Your Plants: The Weird Science Behind It (It Really Works)

You’ve probably heard that singing to your plants helps them grow – but is that actually true? In this episode, we dig into the science behind the myth, from CIA lie detector experiments on houseplants to a MythBusters greenhouse filled with heavy metal. The answer turns out to be more complicated – and more fascinating – than you’d expect. What does sound really do to plants, and what does not happen, despite decades of wishful thinking? We’ll separate the pseudoscience from the peer-reviewed facts. Then we chat with Cliff and Harrison from the Try This At Home MythBusters Rewatch Podcast!

Let’s start not with a sunflower or a tomato plant, but with a human being. In 1962, a man named Cleve Backster hooked up a polygraph machine to a houseplant. Backster was not a botanist—he was a polygraph specialist for the CIA. One day, for reasons not entirely clear, he decided to attach the electrodes of a lie detector to the leaf of his dracaena plant. He then watered the plant and watched the needle on the polygraph graph paper. To his surprise, the pen jumped. This wasn’t the expected resistance of an inanimate object—Backster interpreted it as emotion. In fact, he claimed the plant was reacting to his thoughts. When he thought about burning the leaf with a match, the pen spiked dramatically.

Now, that sounds like something out of a science fiction novel—and in a way, it was. Backster’s “experiments,” which were never peer-reviewed or replicated successfully under controlled conditions, became the basis for a pseudoscientific movement. It was seized on by believers in what would come to be known as the “Backster effect”—the idea that plants can read our minds and react to our emotions.

It’s tempting to dismiss this as 1960s hippie nonsense—and to be clear, it absolutely doesn’t hold up to scientific scrutiny—but it did plant a seed, pun intended. Since then, people have believed that plants are more “aware” than we give them credit for. And one of the most persistent offshoots of that idea is this: if you sing to your plants, they will grow better.

It sounds cute, right? Maybe it feels a little whimsical, a little Disney princess-esque—like if you croon your worries to your pothos, it’ll reward you with an extra inch of growth. And who doesn’t want their ferns to feel loved? But the question remains: is there any truth to it?

Let’s explore both sides.

There’s a common misconception that plants have ears—or that they can “hear” in the way animals do. They don’t have brains. They don’t have nervous systems. So they certainly don’t hear in the traditional sense. But sound is, at its core, vibration. And vibration, it turns out, can have an effect on plant life.

In 2003, a team of researchers at the National Institute of Agricultural Biotechnology in South Korea tested the effects of sound on rice plants. They played classical music, as well as traditional Korean music and frequencies in the 125Hz to 250Hz range, and observed how the plants responded. They found that the sound waves actually activated certain genes in the plants—the same genes involved in their response to light.

In other words, the plants weren’t “listening”—but they were responding physically to the vibration of the sound waves. In fact, the researchers were able to identify specific genes—like rbcS and ald—that were activated under sound stimulation. The vibrations, in essence, were triggering a mild stress response in the plants, which caused them to bolster certain growth functions.

This phenomenon is called mechanotransduction—the process by which cells convert mechanical stimuli into chemical activity. It’s the same basic idea as how our muscles grow after physical stress. In plants, mechanotransduction is most commonly associated with things like touch, wind, and even rain—but it turns out that sound waves, being physical vibrations, fall into that same category.

So…does that mean singing to your plants really does help them grow?

Well, maybe. But not necessarily because of your incredible rendition of Adele. It’s more about the vibration itself than the content of the sound. You could be humming, playing a trumpet, or yelling about the IRS—and your plants might still respond. And this is where things start to get a little muddy, because people hear that and make some wild logical leaps.

Take Dorothy Retallack, for instance. In 1973, she published a book called The Sound of Music and Plants. Retallack, a student at the Colorado Women’s College, conducted a small-scale study in which she exposed plants to different types of music. According to her book, plants exposed to classical and jazz music flourished, while those exposed to rock or heavy metal wilted and even tried to “escape” the speakers.

It’s an evocative image, but the study lacked rigorous controls. It wasn’t peer-reviewed. And more importantly, subsequent attempts to replicate her findings have failed. Scientists like Dr. Daniel Chamovitz, author of What a Plant Knows, have pointed out that plants can respond to mechanical stimulation like sound waves, but the idea that they prefer Chopin to Megadeth is probably just human projection. We love classical music, so we assume our begonias do too.

So what happens when you try to test this in a controlled, scientific setting?

Enter MythBusters.

In a 2004 episode titled “Do Talking Plants Grow Better?”, Adam Savage and Jamie Hyneman set up an experiment using 60 pea plants. They divided the plants into six greenhouses and subjected each group to a different sound treatment: silence, loving human praise, harsh insults, classical music, heavy metal, and recordings of people talking nicely.

The results? Plants exposed to any kind of sound—including harsh insults and metal music—grew better than those in silence. The best growth, surprisingly, came from the heavy metal greenhouse. But here’s the important bit: they controlled for things like soil, water, and light. The only difference was the audio.

So it wasn’t what you say. It wasn’t your emotional connection to the plant. It was the presence of sound itself—vibration again. The plants in silence did worse. Which suggests that yes, sound can play a role in plant growth—but not because your ficus likes being serenaded with show tunes. It’s about the physical effect of sound waves on plant cells.

We’re going to zoom out a bit now, because even though we’ve talked about how vibration affects plants at the cellular level, it leads us into a broader, mind-blowing question: how much do plants sense the world around them?

In recent years, botanists have been gathering more and more evidence that plants aren’t just passive green decorations. They respond to touch. They communicate with each other using chemical signals. They send distress signals when they’re injured. And—here’s the kicker—some plants may even respond to the sound of a predator.

A 2014 study out of the University of Missouri found that when researchers played the sound of a caterpillar chewing to a thale cress plant (Arabidopsis thaliana), the plant responded by producing more defensive chemicals—glucosinolates and anthocyanins. When the researchers played similar sounds, like wind or other vibrations, the plants didn’t respond. It was specifically the chewing sound. Somehow, the plant was able to differentiate between types of vibrations and react accordingly.

Now that’s wild.

It’s almost like plants have a primitive form of “hearing”—not with ears, but with vibration-sensitive cells. Dr. Heidi Appel, one of the authors of the study, said: “Plants have many of the same responses to environmental cues that animals do, but without ears, eyes, or a nervous system.”

So does that mean they can enjoy your singing?

Probably not. But they might react to it in some way. Maybe your lullaby hits just the right frequency to trigger a stress response that causes the plant to bolster its defenses. That might result in increased growth or stronger stems. Or maybe you’re just shaking the air in a way that mimics wind, causing the plant to respond with sturdier development.

There’s also the human factor. Some scientists have speculated that people who talk or sing to their plants may be more likely to care for them in general—watering them consistently, checking for disease, rotating them for even sun exposure. In other words, the talking itself isn’t helping the plant, but the attention is.

As for famous advocates of plant-chatting, you may have heard that Prince Charles famously admitted to talking to his plants—and that they “respond.” In a 1986 interview, he said: “I just come and talk to the plants, really – very important to talk to them, they respond.” He was widely mocked for it, but the statement sparked a surge of public interest in the idea. And honestly, even if it’s not scientific, talking to your plants probably doesn’t hurt.

In fact, some horticulturists even recommend playing music or adding ambient noise in greenhouses, not for the emotional benefit of the plants—but to simulate wind and vibration, which helps them grow sturdier. One study in Ultrasound in Medicine & Biology even suggested that ultrasound frequencies could stimulate seed germination and enzyme activity in soybeans.

Still, a word of caution: not all sound is good. Excessive noise can cause damage to plant cells—especially very high or very low frequencies. Just like too much wind or shaking, it can stress the plant beyond helpful levels. So maybe don’t blast Metallica 24/7.

In the end, what we know is this: sound affects plants. Not because they like your voice. Not because they’re listening. But because sound is physical—and plants are very, very sensitive to the physical world.

So does singing to your plants help them grow?

The internet says it’s true. But it’s probably not your singing that’s doing the trick—it’s the sound itself.

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