A plant does not need a nervous system to notice when it has been touched.
Field Notes
The tiny hairs inside a Venus flytrap register contact and send electrical signals across the plant. One touch is not always enough. It waits for another, as though checking that what it felt was real, before snapping shut.
This is why Venus flytraps appear so often in conversations about plant intelligence. They make visible what is easier to overlook in slower plants: a plant can sense its surroundings, hold information for a moment, and change its behavior in response. Whether that is feeling exactly as we experience it is still unknown—but it is much more than passivity.