|'Double Black Dragon', also known as 'Violacea Plena', and 'Yae Kokyuryu', has double flowers which are violet in color. Popular, aggressive, flowering vine. Pinnate leaves with up to 19 lance-shaped leaflets up to 3 inches long. Top choice for covering arbors or spilling over fences. Blooms in late spring. Flowering not as spectacular as Chinese Wisteria due to prolonged season of bloom. Can become quite large. Twines from right to left.