Inspiration: Monica Gagliano

Dear grapelovers,

When you spend all day working with plants, you might start to ponder the nature of this life form. Are they merely a silent biochemical process emerging from the earth—or is there more to them?

Before Galileo—or more precisely, before the scientific revolution—most people in Europe believed the earth was flat. Anyone who claimed otherwise was ridiculed. It's a similar story with plants: since we don't find a brain in them, we consider them mindless beings.

But then Monica Gagliano, now a professor of plant behavior and evolutionary ecology (University of Sydney / Southern Cross University), came along. She began researching plant intelligence—and was initially ridiculed by her colleagues. However, through a series of elegant experiments, she revealed astonishing plant abilities and prompted us to reconsider the very concept of "intelligence." Her book, "Thus Spoke the Plant," documents her findings.

Plants can learn. In one of her most impressive experiments, Gagliano trained pea plants in a Pavlovian-style setup. The plants were placed in a Y-shaped maze, along with a fan and a light source. Normally, plants grow towards the light. But Gagliano repeatedly paired the sound of the fan with the light until the fan alone became the signal. Later, when the plants had a choice, they grew in the direction indicated by the fan—even when there was no light there. Just as Pavlov's dogs began to salivate at the sound of a bell, the plants had learned to associate a neutral cue with a reward.

Plants have a memory. Another experiment she conducted involved the mimosa (Mimosa pudica), which is known for folding its leaves when touched. Gagliano repeatedly dropped the plants from a low height onto a soft surface. At first, they folded their leaves every time. But after a few repetitions, they stopped—apparently, they had "understood" that the stimulus was harmless. Days and even weeks later, the plants still remembered this lesson and no longer wasted energy on unnecessary defense mechanisms. This is a form of memory and learning that was previously thought impossible without a nervous system.

With such studies, Gagliano has shown that plants possess astonishing, unexpected abilities. They remind us that intelligence can take many forms—and that life is far richer and more subtle than our categories suggest.

The question remains: If plants can surprise us so much, where else might we find hidden intelligence if we only look more closely?

All the best, Hoss