Wisteria

Where it grows

Chinese wisteria (W. sinensis) twines anticlockwise; Japanese wisteria (W. floribunda) twines clockwise — a useful identification feature once the plant is established. Both have naturalised widely outside Asia; the native American wisteria (W. frutescens) is the smaller, less aggressive species favoured in modern North American landscapes.

How to recognise it

A woody climbing vine that can reach thirty metres into supporting trees in the wild, with pinnate leaves of seven to thirteen leaflets. The pendant racemes of pea-shaped flowers hang twenty to fifty centimetres long, with the flowers opening from the top of the raceme down in W. sinensis and all at once in W. floribunda.

Garden & cultural uses

Wisteria demands strong support — mature stems can break wooden trellises and crush rain gutters. Hard summer pruning encourages flowering. The Ashikaga Flower Park in Japan and Kawachi Fuji Gardens are global pilgrimage sites for spring wisteria tunnels in lilac, white, and pink.

In safety

All parts of wisteria, especially the bean-like seeds, contain lectins that cause severe gastric upset if eaten; children should not chew the inviting pods.