Common Name: Mimosa, silk tree
Origin/Ecology: Native from Iran to Japan
Habit: 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.
Leaves: Bipinnately 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. Sensitive leaflets close up when touched and at night. Leaflets fall to the ground after frost, producing no fall colour.
Leaf Arrangement: Alternate
Flowers and Fruit: Fluffy, pink, powder puff flowerheads cover the tree with a long summer bloom. Flowers are fragrant and attractive to bees. Flat bean-like seed pods, up to 7″ long, persist into winter.
Bark: Not noteworthy
Water Use, Soil: Grown in average, medium moisture, well drained soils. 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.
Exposure: Full sun to light shade. Thrives in high summer heat.
Landscape Uses: Attractive but inferior landscape tree. May be used as an accent in areas where soils are poor or alkaline. Avoid planting in areas where wilt is a problem.
Limitations: Wilt is a serious problem in many areas. Also susceptible to mimosa web worm. Self-seeding can produce numerous seedlings. Weak wooded limbs are susceptible to damage from strong winds and ice/snow.
Other Features: Tolerates deer and drought. Flowers also attract butterflies.