Wisteria

Wisteria is a highly floriferous (producing numerous blooms) woody vine that blooms in mid-spring and will grow to 10 to 25 feet depending on the support it is given. Wisteria blooms are highly fragrant and come in a variety of colors ranging from pink to purple to white. These flowers are found in large racemes (long drooping clusters) of about 12 to 18 inches in length. Training into a small tree or shrub requires a significant amount of pruning. The genus name honors Caspar Wistar (1761–1818), an American physician and anatomist on the faculty of the University of Pennsylvania. 

Some Wisteria species such as the Chinese and Japanese species (Wisteria sinensis and Wisteria floribunda respectively) growing in the wild and in the landscape have the potential to compete with its host tree for sunlight, and usually winning. American wisteria (Wisteria frutescens) is much less aggressive and requires less pruning and no risk of introducing an invasive species. This plant is mildly resistant to damage by deer and is toxic to dogs, cats, and horses. 

It can be found in forests and other natural areas. This ornamental vine may be native or exotic and can become weedy in disturbed areas, and by roadsides.

Blooms appear on new growth only. The best time to plant is in the spring or fall when the plant is dormant. It can be grown from seed; however, it may take several years to mature and produce flowers. A cutting is a better choice for reproduction.  

When choosing a plant, please consider the fact that Asian wisterias are more aggressive growers than the North American variety. Distinguishing traits include differences in the seed pods. Asian wisterias have fuzzy seed pods, while North American wisteria has smooth seed pods. Also, the flowers on the North American varieties bloom after the plant has leafed out, while Chinese wisterias will bloom before the foliage opens.  

Insects, Diseases, and Other Plant Problems: Due to its rapid growth and spread, some wisterias can become quite heavy, putting a strain on the object or structure that it is attached to. It can spread in very small nooks and crannies, so placing near a structure such as your home is not advisable.  

Some insects affecting this plant are Japanese beetles, aphids, leaf miners, scale insects and mealybugs. Dieback, crown gall, and leaf spot are some diseases known to affect wisterias.