Redbuds (Cercis spp.) are trees or large shrubs characterized by purple-pink or white spring flowers that appear before the heart-shaped leaves. All redbuds are members of the bean or legume family and one of the most evident family traits is the beanlike seed pods, which generally appear in the fall. The pods are generally brown to black and can be several inches long, depending on the redbud species and variety.
The hanging seed pods generally contain many individual seeds. Browned and somewhat desiccated looking, they persist on the deciduous trees and shrubs after the leaves fall in the autumn. The flowers -- which are generally larger on cultivated varieties than on the various redbud species, are purple-pink or sometimes white -- are another identifier. Pollinated by bees, they are small and pealike and sprout in clusters completely covering parts of the trunk and branches. Trees in the genus can grow to about 30 feet tall.
The best known redbud is the eastern redbud (Cercis candadensis), hardy in U.S. Department of Agriculture plant hardiness zones 4 through 8. The number of available varieties is large and includes "Forest Pansy" (Cercis canadensis "Forest Pansy"), hardy in USDA zones 5 through 9, which features purple young growth that matures to lighter purple or purple-green. The white-flowered "Royal White" (Cercis canadensis f. alba "Royal White"), features larger flowers than other white forms. It is hardy in USDA zones 4 through 9. "Covey" (Cercis canadensis "Covey"), hardy in USDA zones 5 through 7, is a weeping form.
Redbud seed pods are attractive to birds and some wildlife, making the trees and shrubs good choices for habitat or wildlife landscapes. The flowers attract bees, butterflies and pollinating insects and a single redbud might anchor a butterfly garden. The western redbud (Cercis occidentalis) is smaller than its eastern counterpart. Hardy in USDA zones 7 through 9 or 10, its blue-green leaves, pink flowers, distinctive seed pods and drought tolerance make it a good choice for xeriscape or dry gardens or landscapes. Redbuds can also be used as medium-size street trees.
Buy young redbuds from local nurseries, which are most likely to have trees hardy in a specific area. Site new trees carefully, as redbuds do not adapt well to transplanting later. Optimal conditions for flower, leaf and seedpod production include full sun, though redbuds can also tolerate light shade. Plant in well drained soil amended with compost or other organic material -- the trees do not flourish in consistently wet or boggy sites. Mature eastern redbuds have a spread of 25 to 35 feet, so make sure that the chosen site has sufficient room for the tree's growth.