Although it tolerates adverse conditions, the roots rot easily in poorly drained soil. Young plants respond well to fertilizer, but too much fertilizer may minimize the bloom of mature plants. During summer, fast-growing twining shoots may be pruned to prevent development of a tangled mass. Structure pruning in winter helps contain the vines, but should be selective to maximize bloom. The most popular wisteria produce purplish lavender flowers in clusters several inches long.
Various cultivars produce pink, blue or white flowers.
Vines grown from seed are variable and may not bloom as profusely as the parent vine. Japanese wisteria, Wisteria floribunda , is occasionally available, but not as well suited to the climatic conditions of the Santa Clara Valley. If it blooms successfully, it is not nearly as profuse as other wisteria, but the flower clusters are impressive and may be 18 inches long. Although wisteria vines are commonly available, acquisition of specific cultivars may require considerable research. The most classic wisteria are seen in old established landscapes where they have space to grow.