Family: Bignoniaceae

Native to East Asia and North America, these deciduous trees are fast-growing and useful as shade and ornamental trees as they are very attractive when in bloom. They have a round head, large, simple, long-stalked leaves, terminal sprays of hell-shaped flowers mainly in white or pink tones marked with purple and yellow, and long, narrow, bean-like fruit.

Species

C. bignonioides, common catalpa or Indian bean, has large, ovate leaves, downy on the undersides, and sprays of white flowers, similar to foxgloves, which are striped yellow and spotted purplish brown on the inside. It is a wide, spreading tree, 12-15 m (40-50 ft) tall. 'Aurea' rarely grows more than 10 m (33 ft). The attractive golden foliage lasts throughout the growing year and colours a deeper gold during autumn. 'Nana' is a dwarf variety, rarely more than 2 m (6 ft) high, and frequently grafted onto upright understocks to form standards with umbrella-like, dense heads.

Cultivation

Catalpas can be planted in any moderately rich, well-drained soil but will do best in a light, friable soil if well watered in summer. Because of the large leaves, some protection from wind is necessary. Propagate from seed sown in autumn in a garden frame, from softwood cuttings in spring or early summer, or from root cuttings in winter. Cultivars can also be grafted in winter or budded in summer.

Climate

Zone 5 for most species.