Wisteria vines are among the most beautiful and frustrating plants for the home landscape. When in bloom, they are hard to beat for their long tresses of flowers. However, the most common complaint about wisteria is that they may take a long or very long time before they start to bloom.

There are many proposed techniques to overcome this problem but none of them is proven to work on all vines at all times. Some say root pruning helps while others say you should prune the vine back severely to stimulate flowering. Another recommendation is to fertilize with superphosphate but, if this works, it is only because your soils are deficient in phosphorus. A soil test will determine the amount of phosphorus in your soil.

Another theory says that they will grow slower but bloom sooner if planted in sandy soils. The famed plant explorer, E.H. Wilson studied wisterias in their native Japan and claimed that the most floriferous ones grew next to streams. Oh, well.

North America and Eastern Asia are home to about 10 species of wisteria. Of these two, Wisteria sinensis (Chinese) and W. floribunda (Japanese), are by far the most popular for the home landscape.  The other species include W. brachybotrys, W. brevidentata, W. frutescens (American Wisteria), W. macrostachya (Kentucky Wisteria), W. venusta (Silky Wisteria),  W. villosa and W. formosa.

Interestingly, there is a difference between how various species of wisteria twine themselves around things as they climb. Wisteria frutescens, W. macrostachya and W. sinensis (Chinese) twine from left to right as they climb. Wisteria floribunda (Japanese), W. Taiwan and W. venusta climb by twining from right to left.

The genus was named in honor of Dr. Caspar Wistar (761-18I8), Professor of Anatomy at the University of Pennsylvania. For some reason, the spelling was changed somewhere along the line to an er ending rather than ar.