Do Plants Feel Pain? Well, Kind Of
One reason we all love to keep plants in our homes? They add a sense of life to the environment—literally. Plants are living organisms, which means they grow, eat, move, and reproduce, just like humans and animals do. But there are some big differences in how plants engage with their environments, including how they experience and respond to pain.
“Do plants feel pain?” is a fair question, but the answer is a bit complicated. Dr. Elizabeth Van Volkenburgh, professor of biology at the University of Washington, says it might come down to linguistics.
Technically, she says, plants—like any living organism—perceive and respond to touch, including painful touch. Here’s how it works: Both animals and plants have mechanoreceptors in their membranes. When that system is mechanically perturbed—say, if an animal chomps off some leaves from a plant, or you uproot some flowers from your garden—those receptors send messages to the plant’s cells. In that sense, the plant “knows” it’s being eaten or pulled from the ground.
Van Volkenburgh says plants can also respond defensively to physical disturbances like being cut open or wounded. But that doesn’t mean they perceive painful stimuli the same way a human or animal would, with all the emotional connotations that come with it.
“Plants definitely perceive and respond to touch and temperature changes, but I am disinclined to say they ‘feel,’” she says. “The whole business of feeling relies on a brain, and plants don’t have brains.” Plants experience other senses in the same way: They can perceive and respond to light and soundwaves, but they don’t see or hear—those senses rely on nerves and brains, which plants don’t possess.
Van Volkenburgh says there’s actually quite a bit of debate among plant neurobiologists about whether plants do or don’t “feel” pain. Some research using anesthetics on plants suggests that the chemical compounds in anesthesia cause a similar reaction in plants and animals. But Van Volkenburgh says just because a plant can theoretically be numb to pain sensations doesn’t mean it feels pain to begin with. “Plants have physiology that will change if you apply an anesthetic, and that’s about as far as I would go,” she says.
While plants’ pain perception isn’t the same as people’s or animals’, their ability to perceive pain at all brings up another question: Should we treat plants differently, knowing they can sense our touch and other environmental changes? Van Volkenburgh says she considers plant ethics to be a topic worth conversing about.
Since plants are living organisms, she encourages plant-owners to engage with them respectfully. For example, instead of cutting down an entire Christmas tree, she displays and decorates a simple tree branch in her home for the holidays. After Christmas, she throws away the branch, and the tree she cut from will have regrown a new one. Ethics toward plants requires that type of intentionality.
“Bringing a plant into your home can be done with care and respect, ” she says. “Which just means an awareness of what you’re doing.”