Over the hot spring and summer months, weedy Mimosa trees (Albizia julibrissin) stand beautiful along U.S roadsides. During the rest of the year, people pay very little attention to this arboreal Asian beauty that inhabit a vast area from Iran to China (USDA hardiness zones 6-9). YES, this tree can be invasive. Read on.

From late spring through summer, mimosa struts an attractive fine textured green foliage and lovely flowering. It leaves out as late as mid-May in its northern range. Wild seedlings produce pale pink to dark pink feathery blooms from late June thru July. The showy fragrant flowers attract numerous bees and hummingbirds. Fall leaf color is insignificant.

Mimosa grows 20-25 feet tall of equal and broader widths. Under cultivation, it may achieve 35-40 feet high. It is at its best in full sun and in any adequately drained soil. It copes with subpar sites and often overpowering an abandoned urban lot or a roadside fencerow. Two most popular cultivars are:

‘Summer Chocolate’ exhibits fern-like dark purple foliage. Leaves start off green and turn fern-like dark purple. Cultivar grows 20 feet tall and wide, about half the size of the wild green seedling tree. (USDA zones 6-10).

Chocolate Fountain™ is a recently released weeping purple leaf cultivar from Dr. Tom Ranney at North Carolina State University. Deep purple, fern-like foliage graces the pendulous, weeping habit, enhanced by delicate pink flowers in summer. It grows 15-20 feet high/ 15 feet wide; cultivar is an ornate option planted in a patio container. (zones 6-10).

Mimosa tree tends to be short-lived, around 15- 20 years. Trees tend to colonize, depositing loads of seeds that beget lots of seedlings that take flight from miles away. Mimosa tree tends to improve soil tilth and nutrition.

Late winter thru early summer (February-July) is the ideal planting time. Prune out unwanted and dead branches in any season. Over the first two years, water deeply during extreme heat and dry spells. Fertilizing a mimosa tree is unnecessary as roots manufacture its own nitrogen.

Let me emphasize that bees, butterflies, and hummingbirds are attracted to mimosa’s flowers. The fruits are flattened legumes and contain 5 to 16 seeds. Feathery flowers appear in June and seed pods typically mature in August or September. Seeds are widely dispersed by wind, water, or animals.  The seeds contain a neurotoxin that, when ingested, can be toxic to livestock and dogs.