Hong Kong

Hong Kong Orchid Tree

Bauhinia blakeana

Photo of pink flower

General Description / Cultural Significance

The Hong Kong orchid tree, Bauhinia blakeana, is a national emblem of Hong Kong. A stylized version of the flower is depicted on their flag. The tree is a highly desired hybrid with attractive, striking purple flowers that are fragrant, umbrella-shaped and very much resemble orchids even though they are not. It is highly attractive to frenetic hummingbirds. Bauhinia blakeana is a prized ornamental city tree and lines many of Hong Kong’s streets. The people of Hong Kong also associate it with both wisdom and good luck, often using the leaves of the plant as bookmarks when reading and studying.

Climate Change/Conservation Status

For sixteen days starting in the second half of May 2018, the temperatures in Hong Kong surpassed 91 degrees Fahrenheit. A heat wave of such intensity and longevity had never been recorded since Hong Kong began keeping track in 1884.

As of Summer 2021, the temperatures continue to be hot and unforgiving. There are projected to be a very high amount of climate refugees fleeing Hong Kong, as a result of both heat waves and intense flooding events. Both human life and infrastructure is at risk when it comes to the floods that scientists warn about, but adaptive measures have not yet been put in place. Although Hong Kong is part of the Paris Agreement and has said that they aim to achieve carbon neutrality by 2050, there is currently no strategy. Passing policy is made even more difficult because of Hong Kong’s legal and constitutional challenges related to China.

All plants are in danger due to climate change. But the orchid trees are also in danger because their populations don’t possess genetic diversity at all. They are sterile and don’t develop seed pods, only able to be reproduced when humans carefully cut and clone them. Every single orchid tree in existence is thought to come from one single tree in China. This lack of genetic diversity means that if one disease hit them, they would all effectively be wiped out. Scientists are attempting to map the tree’s genome in order to understand it better and have a chance at conserving the much-loved emblematic plant.

Alternate Names
Clever tree
Purple orchid trees

Sources
Asher, Claire. “How a weird hybrid plant ended up on the flag of Hong Kong,” BBC Earth, December 12, 2016. http://www.bbc.com/earth/story/20161209-how-a-weird-hybrid-plant-ended-up-on-the-flag-of-hong-kong

“Climate Action in Hong Kong: Are We Doing Enough?” Liv Magazine, April 7, 2021. https://liv-magazine.com/climate-action-in-hong-kong-are-we-doing-enough/

Gurung, E. “Typhoon season is here—all you need to know in Hong Kong, from signals to free shots”. (2018). South China Morning Post, 2 August 2018.

Khan, Waseem. “The National Flower of Hong Kong: Bauhinia.” Read National.” https://readnational.com/national-flower-hong-kong-bauhinia/

Melwani, Roshan. “Why Hong Kong needs to start planning for an era of climate refugees.” Hong Kong Free Press, July 4, 2021. https://hongkongfp.com/2021/07/04/why-hong-kong-needs-to-start-planning-for-an-era-of-climate-refugees/

Ng, Yupina. “Could rising tides put the ‘Venice of Hong Kong’ underwater?”South China Morning Post. 17 March 2018.

Ocone, L. “Orchids or Butterflies? They’re Bauhinias”. (1992). Sunset, 188, 5: 74.

Sengupta, S., T. May, Z. ur-Rehman. “The Heat Is Coming in Waves and Surges”. The New York Times International. (2018). Published on 31 July 2018.

Ullah, A., S. Iqbal, M. Qasim, F. Iqbal. “Oral supplementation of ethanolic extract of Bauhinia variegata leaves did not disturbed the hematological and serum biochemical profile of adult albino mice”. (2017). Pure and Applied Biology. Vol. 6, Issue 3: 875-863.

Zheng, R., S. Su, H. Xiao, H. Tian. “Polysaccharides and lipids in the developing anthers of Hong Kong orchid tree (Bauhinia blakeana)”. (2017). Trees, 31: 1295-1301.