Floss-Silk Tree

Floss-Silk Trees are large, winter-deciduous trees, native to subtropical South America, and tolerate some frost to about –7°C, when mature. Young trees are more sensitive to cold. They grow to about 18 metres high and about 9 metres wide with horizontal but gnarled branches that shed the palmate foliage in autumn. They are composed of five to seven oval leaflets. After the leaves have fallen, showy pink flowers with curved petals are borne with up to 16 cm in diameter. They are pollinated by butterflies and develop fruits that are reminiscent of small, brown avocados with woody rind. These split open when ripe to release black seeds that are muffled by white, cottony fibres. Like those of Silk Cotton Trees (Bombax ceiba), they are used for stuffing pillows. An edible oil may be obtained from the bean-sized seeds. The dull-green trunk is covered with grey, conical spines, giving it a decorative feature. It becomes bulky with age in its lower third, and eventually achieves the shape of a bottle. The green bark performs photosynthesis before it turns light grey when old. Established trees do well in full sun and require occasional soaking in summer. Good drainage is important and the soil should be fertile. C. speciosa is a magnificent specimen tree for parks and courtyards, where it may be protected from frosts. Its interesting trunk should be admired from close by, and not hidden by shrubs. Maintenance is minimal with occasional pruning every few years. Floss-Silk Trees are best propagated by seeds.