Whenever I encounter an introverted gardener, I engage them in conversation with this question: What wisteria do you recommend for my backyard?
Expect to hear either one of these perspectives. On the one hand, the shy gardener will regale you with spoken images of the multitude of spectacular, sweetly scented chains of flowers borne by Japanese and Chinese wisterias. On the other hand, you may be scolded for considering Asian wisterias, since these deciduous vines escaped cultivation in the Southeast where they’ve become botanical pythons, strangling trees and occasionally felling them with their sheer weight.
Between these two opposing views lies the American wisteria (Wisteria frutescens). This less famous (or infamous) vine is native from the lowland forests and streambanks of Virginia to Florida. Surprisingly, it was the first wisteria introduced to European gardens, even before the Asian wisterias made their debut.
American wisteria blooms about 3 weeks after the Asian types. Its pendulous, rounded clusters of pale lavender pea-like flowers emerge at the branch tips. ‘Amethyst Falls,’ a popular cultivar discovered as a stem mutation by plantsmen Bill and Bob Head in Seneca, SC, produces 4-6 in. long clusters of lavender-blue flowers in April and May on a relatively compact frame. It tends to re-bloom with greater vigor than the species in mid- and late summer. Other noteworthy cultivars of American wisteria include ‘Longwood Purple,’ which has deeper bluish-purple hues, and ‘Nivea’ with white flowers.