Sub-category: Pea family
A woody, deciduous, perennial climbing vine, native to China. It was introduced from China to Europe and North America in 1816 and has secured a place as one of the most popular flowering vines for home gardens due to its flowering habit. It has however become an invasive species in some areas of the eastern United States where the climate closely matches that of China.
It can grow 20 to 30 m long over supporting trees by counter-clockwise-twining stems. The leaves are shiny, green, pinnately compound, 10 to 30 cm in length, with 9 to 13 oblong leaflets that are each 2 to 6 cm long. The flowers are white, violet, or blue, produced on 15 to 20 cm racemes. The flowers on each raceme open simultaneously before the foliage has expanded, and have a distinctive fragrance similar to that of grapes. The fruit is a flattened, brown, velvety, bean-like pod 5 to 10 cm long with thick disk-like seeds around 1 cm in diameter spaced evenly inside; they mature in summer and crack and twist open to release the seeds; the empty pods often persist until winter.
Commonly cultivated, it spreads easily and has become and invasive species in some areas of the eastern US. Blooms in spring, usually reaching peak in mid-May.