This new profuse, lilac flowering variety of wisteria is a cross between Japanese (Wisteria floribunda) and Chinese (Wisteria sinensis) Wisteria. The result is compact racemes laden with fragrant flowers. Wisteria Formosa Issai is a variety with mauve to violet flowers with a central greenish-yellow blotch. They come out in May along with leaves or after they have emerged and are followed by seed-pods. Their pinnate leaves look exotic and densely cover the plant and its support from the ground level. They are light green.
The flexible nature of the wood from this climber requires a support for the first several years. This can be an excellent choice in vertical gardens and it is perfect for training over a sunny wall or stout pergola where the flowers can best be appreciated from below. To enhance flowering it requires ample space for the roots to become well established and it may need pruning twice a year.
Members of the Papilionaceae Family, Wisteria are vigorous hardy woody climbers with twining stems. The scented flowers are lilac blue, produced in short trusses about 20cm long, in early summer.
Wisteria Issai prefers full sun to partial shade, with a South or West facing aspect and should be in a sheltered exposure. Suitable soils include sand, clay, chalk, and loam. Soil should have high moisture holding capacity, but be well drained.
Wisteria x Formosa Issai grows to an ultimate height between 8-12 metres and a spread that can extend wider than 8 metres. This specimen takes 10-20 years to reach its ultimate height.
The Wisteria Issai is an outstanding addition to your landscape, along a wall, over a structure, or on a well-built trellis. Give them lots of room, prune and care for them, and they will reward you many times over with their beautiful colour and fragrance.