Native & adapted

Hong Kong orchid tree

Bauhinia × blakeana

Also known as Hong Kong orchid · Bauhinia blakeana · Orchid tree

A fast, nearly evergreen tree with large magenta flowers from late fall into spring. It is sterile, so it skips the messy seed pods of other orchid trees.

FloweringPollinatorHummingbirdFast growingFrost tender

Landscape layersLower canopy

Mature size20–25 ft tall and 20–25 ft wide

Climate fitUrban core · USDA 9b–10a · Valley suburbs · USDA 9a–9b

Plant spacing15–20 ft from other trees; 10 ft from buildings

FrostLeaves damaged near 28°F; young trees can freeze back below about 25°F.

Special categoriesPOLLINATOR ATTRACTING

Hardiness guidanceUSDA 9b–11; leaves and young branches damaged below about 28°F

Winter chillNone

Typical harvestNot a food plant.

Before you plant

These conditions determine whether it will thrive.

Soil chemistry

Fast-draining soil. In alkaline Phoenix soil it often needs chelated iron and some soil sulfur to keep leaves green.

Required microclimatePlacement is part of the growing system.

Warm, frost-protected spot, such as a south-facing courtyard or near a wall.

Right plant, right place

Will Hong Kong orchid tree grow at your Arizona property?

Branches can be brittle in monsoon winds. Train a strong central structure while young and keep it out of the most wind-exposed corners.

Best regional fit: Urban core · USDA 9b–10a, Valley suburbs · USDA 9a–9b.

Light

Sun exposure

Full sun to light afternoon shade. Young trees appreciate afternoon shade their first summer.

Water

Irrigation

Moderate. Deep water every 7 to 10 days in summer.

Fruit set

Pollination

Sterile hybrid; it does not set seed. Hummingbirds and bees visit the flowers.

Harvest

How to use it

Grown for flowers and shade.

Planting & stewardship

How to help Hong Kong orchid tree thrive

1
Stake lightly the first year and prune for a strong single or low multi-trunk form.
2
Feed with an iron-rich fertilizer in spring if leaves yellow.
3
Cover young trees on frost nights.
4
Thin crowded branches after flowering to reduce wind damage.

Read the horticultural reference ↗