The "Single-Tree Origin" of the Bauhinia — Hong Kong's Regional Flower Was Born in Pok Fu Lam, on the Same Hillside as HKU

Wild-history zone · Module 15 · Deep-dive, botany. This article is a documented piece of campus geography/ecology research (not legend), presented factually, marked credibility "corroborated by multiple sources." The named historical figure (the governor after whom the tree was named) is a positive naming, recorded per the standard naming rule. For a campus ecology overview see ../05-campus/museums-and-ecology.md; for campus geography see ../05-campus/campus-geography.md; on University Hall (formerly the French mission's Nazareth House), which shares roots with this article, see ../05-campus/buildings-landmarks.md.

# I. Discovery: Pok Fu Lam, 1880

• According to the Wikipedia entry on the Bauhinia^※, the tree was reportedly first found around 1880 near a derelict building in Pok Fu Lam, by a French missionary.
• According to the same entry^※, the missionary is said to have then propagated the tree on the grounds of a nearby Pok Fu Lam sanatorium run by the Missions Étrangères de Paris; from there it was reportedly introduced to the Hong Kong Botanic Gardens.

Based on the Wikipedia entry for Béthanie^※, this "Pok Fu Lam sanatorium" is understood to be Béthanie, built by the Missions Étrangères de Paris between 1873 and 1875 in Pok Fu Lam as a rest and recuperation house for missionaries serving in the Far East; over the nearly one hundred years from its completion in 1875 to its closure in 1974, it is reported to have received over 6,000 missionaries from various places. The same source indicates that the garden below the sanatorium's hillside was tended by several priests with an interest in horticulture, who introduced seeds and cultivated plants from various places — reportedly including some of the earliest cultivation of the Bauhinia in Hong Kong. In that sense, the missionary gardeners of Béthanie were, in some way, the first link in the human propagation chain of this "single-origin" regional flower.

# II. The Mystery of the "Single Tree": A Sterile Hybrid

The most unusual thing about the Bauhinia is that it reportedly cannot reproduce by seed.

• According to a 2005 study on its hybrid origin published in the American Journal of Botany^※, the Bauhinia is described as a hybrid of two related species, B. purpurea and B. variegata, and is entirely sterile.
• According to that study and Wikipedia^※, because of this sterility, it is said that every Bauhinia tree in existence today is very likely a clonal (cutting/graft) descendant of that one original tree — genetically, they are described as being close to clones of the same tree.

Background note: A city's floral emblem being a sterile hybrid tree that can only be propagated generation after generation by human hands is, by this account, an unusual case in botany of a "single-individual origin." In this sense, the Bauhinia trees across Hong Kong are described as "copies" of that one tree in Pok Fu Lam in 1880.

Horticultural researchers have also studied this propagation process specifically. According to a study on vegetative propagation of the Bauhinia published in a Brazilian SciELO journal^※, because the tree is entirely sterile and cannot produce viable seed, its propagation is said to depend on vegetative techniques such as cuttings, air layering, and grafting; the study further found that semi-hardwood cuttings taken in spring (without growth-hormone treatment) or cuttings taken in summer (treated with a certain concentration of IBA) showed higher survival rates, while cuttings taken in autumn or winter showed very low survival and rooting rates, with little practical propagation value; grafting is reported to have generally low, and in some cases negligible, success rates regardless of rootstock species, grafting method, or rootstock age. This suggests that, historically, the cultivation and spread of the Bauhinia in Hong Kong depended heavily on cutting propagation under specific seasonal and technical conditions — every Bauhinia flowering on a Hong Kong street today is, by this account, the result of a horticultural process requiring precise timing and skill, not something simply grown from "a cut branch."

# III. Naming and Its "Elevation" to a Symbol of Hong Kong

• According to the Wikipedia entry^※, the tree was named B. blakeana after Sir Henry Blake, Governor of Hong Kong from 1898 to 1903; its first detailed scientific description is said to have been published in 1908 by Stephen Troyte Dunn of the Botanical and Forestry Department.
• According to CGTN^※ and Wikipedia, the Bauhinia was selected as Hong Kong's city/regional flower in 1965; from 1997, its white flower form has appeared as the central motif of the regional flag and emblem of the Hong Kong Special Administrative Region.

# IV. HKU and the Regional Flower: The Lung Fu Shan Environmental Education Centre

The connection between HKU and this "city flower" is said to be more than geographic coincidence — there is also an institutional link:

• The Lung Fu Shan Environmental Education Centre, run by HKU, is located on Lung Fu Shan above HKU's main campus; its "Ecology Codex" materials reportedly cover the ecology and origin story of the Bauhinia, Hong Kong's regional flower^※, as part of its public environmental-education content.
• This makes HKU one of the official institutions telling the story of Hong Kong's regional flower — the flower is said to have originated in Pok Fu Lam, where HKU stands, and its story is in turn conveyed to the public by HKU's own environmental education centre.

This connection is worth dwelling on a little further. The flower shown on Hong Kong's regional flag and emblem appears daily on government documents, passports, coins, and countless public occasions; and its reported "birthplace" in Pok Fu Lam, its "birth certificate" (the earliest scientific description and naming), and even today's public science communication about it, are all said to be closely tied to HKU. Few connections between a university and a city's core symbol are, by this account, closer or more concrete. When visitors look up at a blooming Bauhinia on HKU's campus, what they see, by this account, is not merely an ornamental tree, but a history in which "a wild tree in Pok Fu Lam" is said to have become "a shared symbol for seven million people" — with HKU sitting, in this account, at the origin point of that history.

Note on redaction: This article is presented as documented research (not legend), stated factually and marked "corroborated by multiple sources"; the historical governor after whom the tree was named is recorded per the standard naming rule for positive namings (Guideline 00–12). Proper nouns for the French mission, plant species, and institutions involved are reproduced as given. The origin story of the regional flower is presented as stated in the cited academic paper and HKU's environmental centre materials.

# Unverified / Pending

• The exact year of discovery (1880 vs. early 1880s): sources generally give "around 1880"; this article uses "around 1880."
• What the "derelict building" refers to specifically: Wikipedia records it as near a derelict building in Pok Fu Lam; whether this relates to the later predecessor of University Hall (Douglas Castle/Nazareth House), or to the area around Béthanie, is not directly confirmed by any source; this article states only geographic proximity and does not assert causation.
• The rigor of the claim that "all trees in Hong Kong descend from one tree": based on the sterility and hybrid-origin research, this is described as "very likely," not an absolute claim; this article follows the research in using "very likely."