Chilean mesquite tree is popular in Southern Arizona because of its rapid growth, lower water requirement and ability to provide shade. Native to South America, the Chilean mesquite grows either singly or multi-trunked reaching a mature size of 30' tall with a 40' or greater spread. Its trunk appears twisted with dark, coarse textured bark. Stipular thorns up to 3" long are variably present. Chilean mesquite tree is semi-dormant, from December to April, shedding most of its foliage in the winter. Small, catkin-like flowers appear in the spring. The flowers are followed by light brown, elongated seedpods that ripen and fall to the ground in the summer. Chilean mesquite tree readily hybridizes with Prosopis alba
. Some hybrids are thornless.
Plant the Chilean mesquite tree in full sun. Water it every 7 to 10 days during the first year after planting with little to no supplemental water after establishment. Don't regularly water established mesquite trees, as this causes structurally weak wood and an insufficient root system. Young Chilean mesquite trees do require pruning to shape. This tree produces frequent crossed branches and often grows sprouts around pruning wounds. Prune mature Chilean mesquite tree in the late fall to raise and thin the canopy or to remove occasional suckers and water sprouts. Falling seedpods in the summer may create a litter problem.