white base. They have been observed to attract bees, butterflies and hummingbirds. Its fruit is a flat brown pod long and broad, containing several seeds inside. There are two varieties: Albizia julibrissin var. julibrissin – the typical variety, described above Albizia julibrissin var. mollis – differs in the shoots being densely hairy Habitat, cultivation and uses Original habitats of the tree include regions from Iran (Persia) and the Republic of Azerbaijan to China and Korea. A. julibrissin is widely planted as an ornamental plant in parks and gardens, grown for its fine leaf texture, flowers and attractive horizontal canopy. Other positive attributes are a fast growth rate, low water requirements and the ability to thrive planted in full sun in hot summer climates. It is frequently planted in semi-arid areas like California's Central Valley, central Texas and Oklahoma. Although capable of surviving drought, growth will be stunted and the tree tends to look sickly. As such it should be given infrequent, deep waterings during the summer, which will benefit growth and flowering. The broad crown of a mature tree makes it useful for providing dappled shade. The flower colour varies from white in A. julibrissin f. alba, to rich red-tipped flowers. Variants with cream or pale yellow flowers are also reported. Other cultivars are becoming available: 'Summer Chocolate' has red foliage ageing to dark bronze, with pale pink flowers; 'Ishii Weeping' (or 'Pendula') has a drooping growth habit. A. julibrissin f. rosea There is also a form, A. julibrissin f. rosea (pink silk tree) which has, in the past, been classed either as a variety or as a cultivar. This is a smaller tree, only growing to tall, with the flowers always pink. Native to the northeast of the species' range in Korea and Northern China, it is more cold-tolerant than the typical form, surviving temperatures down to at least . The selected cultivar A. julibrissin 'Ernest Wilson' (also known as 'E.H.Wilson' or 'Rosea') is a cold-tolerant tree with deep pink flower colour. In Japan, A. julibrissin f. rosea is often used for non-traditional bonsai. The name (, Kanji: ) and its variants is a kigo representing the summer in haiku, especially a sleepy summer evening. A. julibrissin f. rosea has gained the Royal Horticultural Society's Award of Garden Merit; likewise the cultivar 'Summer Chocolate'. Other uses The sweet-scented flowers are a good nectar source for honeybees and butterflies. In