Plant of the Week 10/07/2002: Hong Kong Orchid Tree (Bauhinia blakeana)

Plant of the Week 10/07/2002

Bauhinia blakeana S.T. Dunn

Photographed by: Chelsie Vandaveer.
Credits: Photographed Hong Kong Orchid Tree (Bauhinia blakeana) in personal collection
Other Information: Nikon N55, Fuji Super HQ 100

The beautiful Hong Kong orchid tree (Bauhinia blakeana S.T. Dunn) is a member of the Fabaceae or legume family. Like most other legumes, the orchid tree has a symbiotic relationship with Rhizobium bacteria. The bacteria form root nodules and extract atmospheric nitrogen which enables the Hong Kong orchid tree to grow in poor soils.

Hong Kong orchid trees flower in the winter starting before Thanksgiving and continuing until April. Large purple-red flowers cover the entire umbrella-shaped crown for the duration.

Hong Kong orchid trees are sterile and cannot produce viable seed (as far as we know). The tree is considered a chance hybrid, parentage unknown, and unable to reproduce due to lack of chromosomal pairing or other genetic incompatibility.

All Hong Kong orchid trees have been propagated from cuttings; generations of clones descending from the mystery tree discovered about 1880. The original parent tree is said to have been growing somewhere in Canton.

Stephen T. Dunn of the Botanical and Forestry Department in Hong Kong first described the tree in 1908. He named it in honor of Sir Henry Blake, the Governor from 1898 to 1903.

Dr. Lawrence Ramsden with the Department of Botany at the University of Hong Kong has a great page about the many Bauhinia growing in Hong Kong. To learn more, click on the link:

http://web.hku.hk/%7Elramsden/bauhinintro.html