A seed of doubt: Are plants conscious?

Was Princes Charles right all along? Should we really be talking to our plants? Rita de Brún examines the latest research.

A seed of doubt: Are plants conscious?

By Rita de Brún

Was Princes Charles right all along? Should we really be talking to our plants? Rita de Brún examines the latest research.

Are plants conscious? That’s a question that has baffled scientists and philosophers for centuries and continues to do so today. For some, the conundrum is a crock full of fertiliser. Something so daft it merits neither time nor space.

For others it’s a step towards enlightenment, a positive debate acknowledging our awareness of the magnificent sensory capacity of vegetation. Pushing the argument, that all living things are conscious to some extent.

What’s intriguing is how vociferous the opposing sides are in their arguments, given how little is known about the nature of consciousness. University of California academics are arguing the likelihood of plants being conscious is effectively nil. They don’t have the structural complexity to support consciousness, they say.

To bolster the theory that plants might indeed be conscious, Monica Gagliano, an evolutionary ecologist at the University of Australia, presents research to show learned behaviour in plants. Some say plants behave like ‘slow animals,’ fighting for territory, seeking food, growing faster when competitors are near, trapping prey and responding to touch and words.

There’s scientific proof that plants ‘speak’. They emit low and high- pitched sounds, beyond human hearing range. This means they have ‘voices’ in the way that animals do.

Plants hear and smell approaching predators and respond defensively. They emit electrical waves when attacked by caterpillars. In laboratories, when played the amplified sound of caterpillars munching leaves, they respond by creating toxic tasting chemicals in their leaves.

Which side of the debate Prince Charles might support is easy to guess. He famously told the BBC he happily talks to plants and trees and listens to them.

Another who listens is Jimi Blake, gardener extraordinaire at Hunting Brook Gardens in Wicklow. Blake loves to sit by trees and listen to what they say.

I do this wherever I am in the world, and feel the same connection with trees wherever I go. I don’t care where others say the solid, wise advice comes from. For me, it comes from old trees.

“Plants too are connected to one another. They are linked by a massive web under the ground. The mycelium in the soil connects all living plants and trees and mushrooms. The roots connect and intertwine with each other.

“For me, there’s no question but that plants are conscious and we are connected to them,” he says.

June Blake is another great gardener who feels deeply connected to plants. “I do believe plants could well be conscious,” she says.

“There’s so much more to them than we know. We’ve only recently learnt that trees talk with one another via their roots and that they try to protect the trees around them,” she says.

Veteran gardener Helen Dillon is equally convinced: “I certainly believe plants are conscious in some ways. But we don’t necessarily understand how.”

I tend to agree with the gardeners, but not all philosophers would. According to Ben White of Trinity College Dublin’s Philosophy Department: “The vast majority of contemporary philosophers of mind would deny that plants are conscious.”

June Blake at her garden in Tinode, Co Wicklow – she believes plants could well be conscious. Picture: Dara Craul
June Blake at her garden in Tinode, Co Wicklow – she believes plants could well be conscious. Picture: Dara Craul

“The consensus view holds that those kinds of phenomena can be fully explained in terms of chemical processes taking place within plants that don’t require ascribing any conscious experiences to them.

“Plants also just don’t seem to have the kind of physiological apparatus needed to support consciousness,” he says.

Conceding that some philosophers disagree, he says: “The closest thing to a departure from this consensus would be found in philosophers who subscribe to panpsychism. They believe all matter is conscious to some degree, or at least proto-conscious.

"Even they will agree, however, that any form of consciousness possessed by plants will be much less sophisticated than that of humans or other animals, almost certainly not sophisticated enough to raise any of the special ethical issues surrounding the treatment of conscious beings.”

Nobody knows for sure. However, I’m sticking with the ‘conscious’ team. If in the future the debate around whether plants feel pain re-emerges, PETA director Elisa Allen has this advice: “Currently, no one is sure whether plants can feel pain. One day, we may find out they can.

“Today we know eating plants directly, rather than feeding them to animals and then killing those animals for their flesh, requires far fewer plants and doesn’t hurt animals, who we already know for sure feel pain. So for those worried about plants’ welfare, going vegan is the best option,” says Allen.

Respecting plants is not a new idea. Minimising violence to and avoiding injuring them is part of Jainism teaching. Fruitarians share this philosophy to varying degrees. Some eat only those parts of plants that fall, or would fall naturally to the ground.

However, credit where it is due. Thanks to the dietary habits of fruitarians, there are plenty more fish in the sea. Not for them of course, which may be why they’ve their own dating group on Facebook.

Jimi Blake’s book A Beautiful Obsession will be published on September 19 by Filbert Press

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