Desert ironwood is a member of the pea family and its leaves and flowers resemble the sweet pea. This single- or multi-trunk tree reaches heights of twenty-five feet with a nearly equal spread, and is slow-growing. Ironwood is one of the oldest living tree species and provides desert plants and animals with nutrients and shelter, providing shade for quail, doves and small rodents. It produces a bluish-gray, leathery, oval leaf with fine hairs and develops an attractive wide-spreading crown at maturity. The bark on young trees is smooth and gray, becoming wrinkled as the tree ages. The young trees have branches with thorns that disappear as they age. In early spring through late spring, clusters of pea-like flowers appear which range from pale rose to pink or white. The blossoms grow in arches at the end of the branches in a beautiful color display. After the flowers fade, edible, brown seedpods develop, which become a major food supply for wildlife. When given supplemental irrigation, the tree remains an evergreen. In its natural habitat, it sheds its leaves during dry periods to conserve water. The wood of the ironwood is hard and dense and is used for woodworking, charcoal, and firewood. Its heartwood is dark brown and takes a beautiful polish. Use it as a screen, background, buffer tree, or as a transitional plant to separate the desert from more tropical and high water-use plantings. Ironwood is also a good choice for shading a patio or an informal sitting area. The tree is native to the Sonoran Desert in Arizona, where it grows below 2,500 feet in sandy washes, rocky slopes, and valleys. It also grows natively in the southeastern California deserts, Baja California, and Sonora, Mexico.
The tree is drought-resistant, prefers well-draining soil, full sun, and reflected heat. It is hardy to about twenty degrees Fahrenheit and needs some protection from frosts when young. Do not over-water this tree or plant it with other vegetation that requires a lot of irrigation. Over-watering of the ironwood can cause its demise. This dramatic plant produces very little litter and is relatively easy to grow and maintain.