I’m going to tell you something that might sound strange. Plants can


see you. Plants don’t have eyes, but they


can see you. T ey know if you’re near them. T ey can sense light. Seeing is just one way plants learn


about their world. T ey can feel and smell, too. You might think I’m joking. I’m not. I’m a scientist who studies plants. For many years, I’ve asked this


question: “What do plants know?” Many other scientists have asked it, too. We have observed plant behavior. Here’s what we have learned. Plants have senses.


A Sense of Sight Years ago, there was a scientist named Charles Darwin. Darwin observed that plants bend toward light. So he came up with a hypothesis,


or explanation. He guessed that the tip of a plant senses light.


The Experiment Darwin needed a method to prove his hypothesis. His method was an experiment. He planted five seeds that grew five shoots. He allowed the first shoot to grow normally. T en he snipped off the tip of the second shoot. He put a dark cap over the tip of the third shoot. Next, he put a glass cap over the tip


of the fourth shoot. He covered the middle part of the fiſt h shoot. T en he waited and watched. Here’s what he saw. T ree of the


shoots bent toward the light. T e shoot without its tip didn’t. T e shoot with the dark cap on its tip didn’t. From these results, he made a conclusion. T e tips of plants do sense light. Other scientists repeated his study and got the same results.


A Sense of Touch Plants can feel, too. T ey don’t feel pain. Yet, they can tell hot from cold. T ey can feel the wind and the rain. T ey can feel your touch. We know by observation. To


learn about a plant’s sense of touch, scientists observed many plants.


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