Culture
Easily grown in average, medium moisture, well-drained soils in full sun to light shade. Best flowering occurs in full sun. Prefers rich, light soils. Tolerates a wide range of soils, however, including poor ones. Tolerates alkaline conditions. Tolerates drought, but best growth occurs with regular watering. Thrives in high summer heat. Not reliably winter hardy in USDA Zone 5.
Noteworthy Characteristics
Albizia julibrissin, commonly called mimosa or silk tree, is a fast-growing, small to medium sized, deciduous tree that typically grows in a vase shape to 20-40’ tall with a spreading, often umbrella-like crown. It is native to Asia (Iran to Japan). It has been widely planted in the U. S. as an ornamental and has escaped cultivation and naturalized in many areas of the southeastern U. S. and California. In the wild, it is typically seen growing in vacant lots, waste areas, clearings, wood margins, fields and along roads. It can be quite invasive in watersheds where water currents carry and distribute the seeds downstream. It is noted for its bipinnate compound dark green leaves (to 20” long). Each leaf has 10-25 pinnae, with each pinnae having 40-60 tiny leaflets (to 1/4” long). Leaves have a fern-like appearance. Fluffy, pink, powder puff flowerheads cover the tree with a long summer bloom. Flowers are fragrant and attractive to bees. Flowers give way to flat bean-like seed pods (to 7” long) which persist into winter. Sensitive leaflets close up when touched and at night. Leaflets fall to the ground after frost, producing no fall color.
Genus name honors Filippo degli Albizzia, 18th century Italian naturalist, who introduced the genus to Italy in 1749.
Specific epithet comes from the Persian word gul-ebruschin meaning floss silk in reference to the flowers.
Problems
Wilt is becoming a serious problem in many areas. Also susceptible to mimosa web worm. Self-seeding can produce numerous seedlings. Falling leaves, flowers and seed pods can pose significant clean-up problems if trees are planted near homes. Weak wooded limbs are susceptible to damage from strong winds and ice/snow.
Uses
Generally considered to be an attractive but inferior landscape tree. May be used as a lawn accent in areas where soils are poor or alkaline. Avoid planting in areas where wilt is a problem.