Mimosa trees are deciduous, fast-growers that spread in delicate, lacy foliage. They grow fragrant, puffy, pink-orange blooms in late spring to early summer. Mimosa trees are popular terrace and patio trees. These tropical-looking trees provide light shade during their life span of 10 to 20 years.
Orange flowering mimosa trees, sometimes referred to as silk trees, are generally available in areas within USDA Plant Hardiness Zones of 6B through 9. According to the Forest Service Department of Agriculture mimosa fact sheet, these trees are hardy across the western and southern United States, and in parts of the eastern United States. They grow to be 15 to 25 feet tall, with a spread of 25 to 35 feet. Their foliage is green and does not change color in the fall. These trees produce numerous elongated seed pods that are brown, hard and 3 to 6 inches long. Mimosa trees do not have thorns.
Orange flowering mimosas grow best in full sun. They grow well in most types of soil, but prefer soil that is slightly alkaline. They have a high salt tolerance and grow well in drought situations. They do, however, have deeper green and lusher foliage when they receive adequate moisture. These trees require pruning in order to develop a strong trunk and branch system. Since the branches tend to droop, pruning is required to allow access for vehicular and foot traffic. Mimosa trees are not particularly showy during the fall and winter months.
Problems with Mimosa Trees
The bark of mimosa trees is thin and easily injured. Because of their weak and brittle wood, they are prone to breakage, especially during stormy weather. In addition to the risk of breakage, these trees have roots that can interfere with grass maintenance and even lift sidewalks and patios. Another problem with orange flowering mimosa trees is the litter caused by their foliage. According to the Forest Service Department of Agriculture mimosa fact sheet, some cities have passed regulations against the planting of this species because of the weed potential. Also, the seed pods of mimosa trees harbor webworms and intensify vascular wilt, a disease that can spread from one mimosa to neighboring ones. Wilt is oftentimes fatal to the infected tree.