Plants That Move

No, plants do not have legs, but they do move. Although I don’t see it happen, each week my African violet leaves lean toward the light requiring me to straighten them with a quarter turn. I also don’t see the prayer plants fold their leaves each night and reopen them each morning.

Usually, plant movement is very subtle. Yet, there are a few plants that will move right before your eyes. Here are some examples. 

When I was a kid, I remember watching with awe as Mexican jumping beans leaped above my hand. In this case, it isn’t the plant’s seed that is jumping but rather an insect inside it. The “bean” jumped in my hand because the moth larvae inside was trying to get away from my warm hand to a cooler location. Too much heat can cause the caterpillar to dry out and die. Though called beans, they are seeds of a shrub that is native to Mexico. 

While visiting my son Derek in Costa Rica a few years ago, I saw mimosa sensitive plants growing in their natural environment near a volcano. Sensitive plants immediately fold their leaves inward when touched. This is a defense strategy thought to remove harmful insects or to scare herbivores. The leaves quickly roll back out and resume their normal growth processes.

Sensitive Plant growing in Costa Rica

Some plants have parts that move quickly. I loved showing my boys the exploding jewelweed seeds during woodland hikes. Jewelweed, also called touch-me-not, is a type of native impatiens that grows in moist places. The fruit explodes when ripe to distribute its seeds. You’ll find both yellow and orange touch-me-nots growing in Illinois.

Orange Jewelweed (Impatiens capensis)

Most people are familiar with the Venus Flytrap. It is one of many carnivorous plants. Most plants get their food from nutrients in the soil, but a carnivorous plant also eats meat. Carnivorous plants grow in wet, boggy soils where plants have trouble obtaining the nitrogen, so they must supplement their diet with insects.

The mean-looking Venus flytraps have leaves that resemble small mouths that are lined with lots of teeth. When an unsuspecting insect walks across small triggering hairs inside the “mouth,” the leaf bites down to trap the insect. It then releases digestive enzymes to digest parts of the insect. After a few days, the trap opens back up and waits for its next victim.

There are many other types of carnivorous plants. You can learn more about them by watching the University of Illinois Extension Four Seasons Gardening YouTube video Cultivating Carnivores. University of Illinois Horticulture educator Ken Johnson discusses why carnivorous plants have evolved to ‘eat’ meat, the different ways carnivorous plants go about capturing their prey as well as their unique care requirements.

Published in Canton Daily Ledger Column on 9-9-2017