The Chinese wisteria (Wisteria sinensis alba), is a deciduous vine that grows vigorously to 25’ or more and features 6-12” long white violet, or blue flower clusters or racemes which bloom in April-May when the foliage is just beginning to expand. Flowers give way to pendant, velvety, bean-like seed pods (4-6” long) which ripen in autumn and may persist hanging from the vines into winter. It has compound leaves (each leaf typically with 7-13 leaflets). Over time, the stems of this vine become twisted, trunk-like and massive. The Chinese Wisteria was brought from China to Britain in 1816 from where it spread to mainland Europe and North America. The vine is named after Caspar Wistar (1761-1818), professor of anatomy at the University of Pennsylvania. All parts of the plant contain a glycoside wisterin that if ingested may cause vomiting, stomach pains, and diarrhea. It has become an invasive species in some areas of the United States where the climate closely matches that of China. The specific epithet means “free flowering” or “producing abundant flowers”. Wisteria was brought to the U.S. in 1830’s. The plant is long-lived, over 50 years.
Common name: Japanese Wisteria
Scientific Name (family and order): Wisteria floribunda (Willd) DC. (Fabaceae, Fabales)
Species Origin: Japan
New Jersey Status: USDA Introduced
Habit: A woody, deciduous twining climber (liana). The plant may grow over 90’covering many supporting struture using clockwise-twining stems. The plant may be trained as a multi-stemmed shrub or small tree.
Habitat: Zone 4 – 9.
Leaves: Deciduous, Pinnately Compound, Alternate. The foliage is made of shiny, dark-green, pinnately compound leaves, 5 – 15” long. The compound leaves are made of 9 – 13 oblong leaflets that are each 1 -3” long.
Flowers: Perfect. Wisteria floribunda (compared to W. sinensis) is spectacular for its long racemes which can reach nearly two feet. The racemes bear clustered white, pink, violet or blue flowers in early to mid spring. The floral fragrance is reminiscent of grape.
Fruits and seeds: The bean-like seed pods are brown velvety 2 – 6” long; they mature in Summer and pesist until winter. The pods are poisonous.