WSU Clark County Extension

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Silk Tree

Scientific name: Albizia julibrissin

Type:Deciduous tree
Plant Requirements
Zone:6 to 9
Sun:Full sun
Plant Characteristics
Height:30 ft
Width:30 ft
Bloom:Summer flowers
Bloom Time:June to August
Bloom Color:Pink
Additional Characteristics



Wildlife value

Description Gardeners plant the Silk Tree (also known as Mimosa) for its crisp, clean compound frond-like leaflets and pink, pin-cushion fragrant flowers that cover the tree during the summer.

This is a deciduous tree that grows to a height of 30’ and a similar spread. Mature trees take on a wide V-shaped crown when grown under full sun out in the open. Young trees grow very quickly (2’ or more per year). Mimosa tree is slow to leaf out in the spring. When it finally does it bears alternate, bi-pinnately compound leaves which are 10”-20” long. Leaves are comprised of leaflets, consisting of has 20-30 pairs of pinnae, arranged oppositely. The pinnae are approximately 3/8” wide. The foliage is medium green in color all season long. There is no notable fall color.

In June flowering commences. Flowers appear as rounded pink fluffy heads all through the canopy. Individual flowers consist of long (1” or longer) pink stamens arranged in a brush-like fashion. The blossoms are fragrant and seemingly drip with nectar, attracting hummingbirds, honeybees and butterflies.

Flowers give rise to flat, bean-pod like fruit pods

Silk Tree prefers full sun, transplants readily, and is considered very adaptable to a host of different site and soil conditions. This species is now naturalized on the east coast of the United States. In a yard setting, the falling leaves, flowers and seed pods from the mimosa can pose a significant clean-up problem, especially if the tree is planted near a patio, deck or walkway.

In the Northwest this tree is susceptible to nectria canker (Nectria cinnabarina) which leads to limb die-back. The presence of bright pink to coral-red fruiting bodies all along the surface of the dead limbs is the sign of the disease. Once infected the only recourse is to prune out the dead limbs. Don’t leave pruning stubs.
For assistance, contact Dr. Charles Brun (, (360) 397-6060 5701
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