Edward F. Gilman, Dennis G. Watson, Ryan W. Klein, and Deborah R. Hilbert
Introduction
This fast-growing, deciduous tree has a low branching, open, spreading habit and delicate, lacy, almost fern-like foliage. Fragrant, silky, white puffy pompom blooms, two inches in diameter, appear in abundance from late April to early July creating a spectacular sight. The tree produces numerous seed pods and harbors insect (webworm) and disease (vascular wilt) problems. Although rather short-lived (10 to 20 years), mimosa is popular for use as a terrace or patio tree for its light, dappled shade and tropical effect. Its deciduous nature allows the warming sun to penetrate during the winter. This species is considered invasive and is not recommended for planting in Florida.
Growing best in full sun locations, mimosa is not particular as to soil type but has low salt-tolerance. Grows well in acidic or alkaline soil. Mimosa tolerates drought conditions well but has a deeper green color and more lush appearance when given adequate moisture. The blooms, leaves, and especially the long seed pods can create a litter problem. Also, the wood is brittle and has a tendency to break during storms, although usually the wood is not heavy enough to cause damage. Typically, most of the root system grows from only two or three large-diameter roots originating at the base of the trunk. These can raise walks and patios as they grow in diameter and makes for poor transplanting success as the tree grows larger.
Unfortunately, mimosa (vascular) wilt is becoming a very widespread problem in many areas of the country and has killed many roadside trees. Despite its picturesque growth habit and its beauty when in bloom, some cities have passed ordinances outlawing further planting of this species due to its weed potential and wilt disease problem.
Several other cultivars exist: 'Rosea' ('Ernest Wilson') has bright pink flowers, is hardier than the species, and is 10 to 15 feet in height; 'Rubra' has deep pink flowers. 'Charlotte', 'Tyron', and 'Union' are reportedly wilt resistant and might be coming into production in selected nurseries in some areas. None are recommended for use in Florida because the species is invasive.
Mimosa readily germinates from its abundant seeds but the wilt resistant trees must be increased by root cuttings.
Pests
Problems include cottony cushion scale, mites, and mimosa webworm.
Diseases
Mimosa (vascular) wilt is quite a problem and is fatal. It can spread to adjacent mimosas by root grafts.
Literature Cited
Fox, A.M., D.R. Gordon, J.A. Dusky, L. Tyson, and R.K. Stocker. 2008. IFAS Assessment of Non-Native Plants in Florida's Natural Areas: Status Assessment. http://plants.ifas.ufl.edu/assessment/pdfs/status_assessment.pdf (November 16, 2012)
