Albizia lebbeck siris

Credit: Forest & Kim Starr

Flowers and fruits Albizia lebbeck

Credit: Forest et Kim Starr

Albizia Lebbeck leaves

Credit: Lies van Rompae

Yellow flower Albizia lebbeck

Credit: Lies van Rompae

Albizia lebbeck trunk

Credit: J. M.Garg

Albizia lebbeck, siris

Prized in joinery for its black wood, Albizia lebbeck is also cultivated as an ornamental tree. This species, native to India and Myanmar, has a flared habit and a highly decorative pompon bloom.

How to recognize the siris (Albizia lebbeck)?

Albizia lebbeck has a splayed habit and can reach 30 meters in height in its natural habitat. It grows more modestly when cultivated in temperate climates.

The upright trunk is covered with rough gray to brown bark. It can measure up to 60 centimetres in diameter. The numerous branches form a parasol-shaped crown.

The green, bipinnate leaves are smaller than those of the Rain Tree (Albizia saman). They do not exceed fifteen centimetres in length. They are divided into one to four pairs of pinnae, each with between six and eighteen leaflets.

Albizia lebbeck is often grown for the shade its foliage provides in summer. It is also much appreciated for its egret-like flowering. The flowers' numerous stamens, gathered in panicles, form white, cream or pale yellow puffs.

The tree also produces a fruit: a yellowish pod 20 to 30 centimetres long, containing between six and twelve seeds. When the wind blows, the pods rustle, their murmur resembling the voice of an old woman. This is why, in some countries, Albizia lebbeck is known as an old woman's tongue.

The fruit is said to be toxic if ingested by humans or animals. The flowers can also provoke allergic reactions.

Our maintenance tips

Siris do not need watering when well established. However, in times of drought, they may need watering. You'll notice it right away:
the leaves turn yellow when the tree is thirsty.

We recommend that you plant your tree in the ground, so that it can develop properly. If you have no other option than to plant your Siris in a pot, transplant it to the ground when it is two or three years old, so that it can continue to grow.

Watering

Water your Siris when the soil has dried deeply. Use water at room temperature to avoid damaging the roots. If you can, use rainwater or non-calcareous water.

Never leave water standing in the saucer or planter, as this will rot the roots.

Spray

Your siris hates wet foliage. You must not mist the plant.

Repotting

Obtain a pierced pot larger than the root ball. Choose a terracotta model. This material optimizes drainage and limits the risk of root rot in the event of excess water.

Fill the bottom with clay balls or gravel.

Then add a layer of universal or Mediterranean potting soil. Plant your Siris in the center. Fill in with substrate. Do not bury the collar.

Tamp and water to remove air bubbles. You can mulch the base with a mineral material to keep the soil cool.

Fertilization

To promote the growth of your Albizia lebbeck, apply fertilizer in spring and summer.

Apply flowering tree fertilizer to promote growth and flowering.

Prune

Pruning is especially necessary for young trees(up to three years old). Always use clean, sharp pruning shears to promote healing and prevent the spread of disease.

Start by cutting away dead or diseased branches. Then carry out training pruning. Remove intersecting twigs and cut back upright stems. This will help the tree develop its spreading habit.

Plantation

When the risk of frost has passed, it's time to plant.

Siris have a very spreading habit. Plant your tree in isolation, away from your home and other shrubs, so that it can develop its crown. Choose a sunny spot, sheltered from strong winds.

Soak the root ball of your Albizia lebbeck in water. Meanwhile, dig a hole twice as wide and deeper than the root ball. Remove stones and weeds. If your soil is heavy, you can add gravel or pozzolan to the bottom to improve drainage.

Plant your plant in the center. The collar should be level with the ground. Fill the hole with garden soil. You may mix it with compost to enrich it, or gravel to lighten it.

Tamp lightly and water well to help the roots take hold.

Diseases / Threats

Whiteflies

Red spiders

Mealybugs

Information

Family	Fabaceae - Fabaceae
Type	Albizia - Albizia
Species	Siris - Albizia lebbeck
Lifecycle	Perennial
Foliage	Evergreen
Exposures	Sun Half-shade
Substrats	Calcareous earth Humus soil Sandy soil
Planting method	Open ground
Categories	Tree Flowery
Tags	Fritillary Toxic
Origins	South Asia Southeast Asia
Hardiness (USDA)	9b
Leaf color
Flower colors
Fruit color