The Hong Kong Orchid Tree... Is not an Orchid

Following the handover of Hong Kong to the People’s Republic of China, the newly created Special Administrative Region (S.A.R.) officially unveiled its new flag, which features a stylized Bauhinia × blakeana flower on a red background. Yet, despite its common name—the Hong Kong Orchid Tree—Bauhinia × blakeana is not an orchid.

The Hong Kong Orchid Tree is the result of an accidental yet natural interspecific cross-pollination that occurred in Pok Fu Lam, on southwestern Hong Kong Island. It arose between Bauhinia variegata (the Camel’s Foot Tree), which produced the pollen, and Bauhinia purpurea (the Purple Camel’s Foot Tree), which acted as the female parent.

Both parental species belong to the Fabaceae family—commonly known as the legume, pea, or bean family—which means that Bauhinia × blakeana also belongs to the Fabaceae family. In other words, rather than being an orchid, the Hong Kong Orchid Tree is a close relative of peas, beans, and lentils.

The confusion stems from its large, vibrant magenta flowers that look, smell, and feel strikingly similar to true orchids. In fact, this confusion applies to the entire Bauhinia genus. When early botanists first encountered Bauhinia, they used "orchid" as a descriptive nickname rather than a biological classification. As a result, the Hong Kong Orchid Tree inherited the "orchid" moniker from its parental lineage.

Interestingly, because Bauhinia × blakeana is a hybrid, it is completely sterile. This means that all Bauhinia × blakeana trees that have ever existed are exact clones of the original specimen discovered by French missionaries in Pok Fu Lam in the 1880s.