Why Vines Twine

Have you ever wondered what makes a vine twine? It certainly is amazing to watch beans, philodendrons, wisteria and other twining vines wrap their stems around a wire, post or other support and climb upward toward the sky.

This circular growth is called circumnutation. The genetics of vining plants cause them to grow faster near the tip of the stem.  These lightweight tips have longer spaces between leaves allowing more space for the vines to wrap around supports.

When the stem touches a structure the cells on the outside of the stem grow longer than those in contact with the support. This causes the stem to curl and wrap around the support.  As the weight of the lower plants pull on the stem tips they tighten their grip around the support.

Even more fascinating – is some vines like Chinese wisteria twine clockwise while others like Japanese wisteria twine counter-clockwise.

A bit more information:  This type of circular growth in plants is called circumnutation. Many theories of why some vines twine clockwise and others counter-clockwise have been pursued, but the answer appears to be in the plant’s genes. If interested, check out these websites:

Kenyon College - Thigmotropism in Tendrils

How Plants Climb - All About Vines and Other Climbing Plants