Hong Kong orchid tree Bauhinia × blakeana
Hong Kong orchid tree (Bauhinia × blakeana) is an evergreen perennial tree in the Fabaceae family, native to A sterile hybrid found in Hong Kong around 1880 (B. purpurea × B. variegata). It grows 6–10 m (20–33 ft) tall and 6–9 m (20–30 ft) wide, wants full sun and moderate water, and is hardy to about -1 °C (30 °F). Space plants about 6 m (20 ft) apart.
Plan Hong Kong orchid tree in your garden →
Free. Draw your beds, then watch it grow through the year in 2D and 3D.
Hong Kong orchid tree at a glance
| Type | Perennial tree, evergreen |
|---|---|
| Family | Fabaceae |
| Mature height | 6–10 m (20–33 ft) |
| Mature spread | 6–9 m (20–30 ft) |
| Spacing | 6 m (20 ft) centre to centre |
| Sun | Full sun, at least 6 h of direct sun a day |
| Water | Moderate; drought tolerance moderate, waterlogging tolerance low |
| Soil pH | 6–7.5 |
| Cold hardiness | About -1 °C (30 °F) once established (roughly USDA zone 10) |
| Heat stress | Likely above about 40 °C (104 °F) |
| Flowering | from about October for 13–21 weeks (northern hemisphere; later in cold climates, earlier in warm ones) |
| Wind tolerance | Low |
| Pollinator value | High |
| Edible | Not grown as food |
| Native to | A sterile hybrid found in Hong Kong around 1880 (B. purpurea × B. variegata) |
| Common in gardens of | 🇨🇳 China, 🇹🇭 Thailand, 🇸🇬 Singapore, 🇺🇸 United States |
Is Hong Kong orchid tree toxic?
- People: not known to be toxic
- Cats: not known to be toxic
- Dogs: not known to be toxic
No toxicity reported in ASPCA or standard poison references.
If a child or pet may have eaten part of a plant, call a poison centre or vet straight away.
Companion planting: what to grow with Hong Kong orchid tree
Good neighbours
- good With Sweet corn: "Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils. Evidence C
Keep apart or take care
- caution With Alliums (onion family): Onions, garlic and leeks are said to stunt beans and peas (allium root exudates may reduce nodulation). Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
- caution With Alliums (onion family): Beans and peas are traditionally kept away from onions, garlic and leeks. Traditional companion-planting advice; controlled trials are few, so treat it as a soft preference. Evidence D
- caution With Fennel: Fennel is reported to suppress beans and peas growing next to it. Evidence C
See Hong Kong orchid tree in a botanical garden
It grows in this sample garden, which you can walk through in 3D:
- Fairy Lake Botanical Garden (2 plants)
Questions about Hong Kong orchid tree
- How far apart should I plant Hong Kong orchid tree?
- About 6 m (20 ft) apart, centre to centre. A mature plant spreads 6–9 m (20–30 ft).
- Does Hong Kong orchid tree need full sun?
- Full sun: at least 6 hours of direct sun a day.
- How much water does Hong Kong orchid tree need?
- Moderate water. Drought tolerance is moderate and waterlogging tolerance low.
- How cold-hardy is Hong Kong orchid tree?
- It tolerates about -1 °C (30 °F) once established, roughly USDA zone 10.
- When does Hong Kong orchid tree flower?
- From about October for 13–21 weeks (northern hemisphere; later in cold climates, earlier in warm ones).
- Is Hong Kong orchid tree poisonous to cats and dogs?
- For cats it is not known to be toxic; for dogs not known to be toxic; for people not known to be toxic. No toxicity reported in ASPCA or standard poison references.
- What grows well with Hong Kong orchid tree?
- "Three sisters": climbing beans use corn as a support and fix nitrogen; the benefit to the corn is modest but real in low-input soils.
Sources and evidence
Evidence grade B (B: extension service or peer-reviewed).
- Plants of the World Online (taxonomy, native range), Royal Botanic Gardens, Kew
- UF/IFAS Extension tropical and subtropical fruit and landscape publications, University of Florida
Notes and assumptions
- Two-lobed "camel's-foot" leaves; orchid-like magenta flowers from November to March; on Hong Kong's flag. Sets no seed.
Reference values for planning, not horticultural, veterinary or medical advice. Varieties, soils and local climates differ: check with a local nursery or extension service.
Related plants
- Bush bean Phaseolus vulgaris
- Garden pea Pisum sativum
- Sweet pea Lathyrus odoratus
- Runner bean Phaseolus coccineus
- Broad bean (fava) Vicia faba
- Lima bean Phaseolus lunatus
- Cowpea (black-eyed pea) Vigna unguiculata
- Yardlong bean Vigna unguiculata subsp. sesquipedalis