Family: Caesalpiniaceae

From southern Europe, western North America and Asia, these hardy, deciduous trees, 5-15 m (16-50 ft) tall, produce an abundance of pea-shaped flowers in shades of purple, pink or rose, and sometimes white. Usually the flowers appear in clusters or sprays along the bare branches before the leaves, followed by beautiful pods which remain on the tree for a long time. The leaves on most species are similar to those of Bauhinia, but more heart-shaped. The species are reliable bloomers in dry situations.

Species

C. canadensis, zone 4, Eastern redbud, is a splendid tree when in flower. It grows 17-12 m (23-40 ft), with rosy flowers 1 cm O/c in) long. 'Alba' has single white flowers and 'Plena' produces double flowers.

C. chinensis (Synonym: C. japonica), Chinese redbud, zone 6, grows 15-17 m (50-56 ft) and has purple-pink flowers, 2 cm (¾ in) in length, and 12 cm (5 in) long seed pods.

C. occidentalis, western redbud, zone 7, has a shrubby habit, growing to around 5 m (16 ft). It produces red flowers, 2 cm (¾ in) long, and 6 cm (2½ in) long seed pods.

C. siliquastrum, Judas tree, zone 6, to 12 m (40 ft), makes a lovely garden subject, with its profuse clusters of rosy purple to pink flowers and 10 cm (4 in) long pods. The foliage colours in autumn. This species prefers hot, dry summers and frosty winters.

C. f. albida has white flowers.

Cultivation

The species like a deep, well-drained loam, but will grow in most soils. Prune lightly and propagate by cuttings, layering or seed. Cuttings of dormant hardwood are reliable but may be slow to root.

Climate

There are species suited to various climatic zones.