The popular wisterias that bloom so profusely before their new foliage appears in spring are Chinese wisteria, Wisteria sinensis. Others specie are rare. The impressively longer floral trusses of Japanese wisteria are not as abundant, and bloom late amongst developing foliage. American and Kentucky wisteria are more docile small vines, but their floral trusses are both short and late.
Chinese wisteria is also the most fragrant and the most colorful of the wisterias. Lavender is still the most popular and traditional color. White, pink, sky blue and darker almost purplish lavender are also available. The floral trusses, known as racemes, get from half a foot to two feet long. Double flowered cultivars never became too popular because the fluffier blooms are not as elegant. The aggressive vines can reach the tops of tall trees. They rarely strangle limbs or young tree trunks, but have the potential to do so. They are more likely to crush fences and lattice. Wisteria really needs sturdy trellises and specialized pruning for confinement. Vines that grow from seed may take many years to bloom. The pinnately compound leaves turn pale yellow before falling in autumn.