- Division: Tracheophyta
- Class: Magnoliopsida (dicotyledons)
- Order: Fabales
- Family: Fabaceae (legumes)
- Genus: Bauhinia
Orchid trees don't bear orchids—but they do bear flowers that resemble the blooms of certain orchids. The lovely blossoms are also attractive to hummingbirds. The Bauhinia genus includes hundreds of varieties of trees, shrubs, and vines that grow mostly in tropical regions around the world. Some are evergreen, and some drop their leaves during winter or drought.
An orchid tree's thick, leathery leaves are about 2 to 6 inches (5 to 15 centimeters) wide, and deeply lobed. But this tree is mostly prized for its showy flowers, which may be purple, pink, red, orange, yellow, or white, depending on the species. Bauhinia blooms are "perfect," that is, they bear both male and female parts on the same flower. Some cultivated orchid trees are sterile, but on those that are reproductive, flowers give way to long (more than three inches, or seven centimeters) seedpods that start out green and turn brown. When fully dry, a pod springs open, each half forming a spiral, to release the flat, brown seeds inside.
Fast growers, orchid trees typically reach heights of 20 to 40 feet and can be almost as wide as they are tall. Some, like the orange- and yellow-flowering B. kockiana of Malaysia, are climbers that need a strong support. There is a tendency for orchid trees to sprout multiple trunks, and for branches to extend and then droop. Most trees flower in late winter through early summer.
Orchid trees like warmth; most don't tolerate frost. In the US, they grow in Hawaii, Southern California, Texas, Louisiana, and Florida, where they like full sun. If the soil is too alkaline, they'll let you know: their normally bright green leaves turn yellowish.
The International Union for Conservation of Nature (IUCN) has assessed 34 species of Bauhinia, and 11 of those are Endangered or Vulnerable, threatened by livestock, agriculture, or logging. One, Bauhinia haughtii, is found only in coastal Ecuador. Just 30 wild-growing individuals remain, in a protected area, but the plants have been cultivated at the Ecuadorean National Herbarium and the Missouri Botanical Garden.
Cow's Hoof Tree
This beautiful Brazilian Bauhinia is known as the cow's hoof tree, because its double-lobed leaves resemble a cow's hoof. One of the hardiest orchid trees, it blooms in spring and summer. You can find this at the Zoo, along Tiger Trail.
Hong Kong Orchid Tree
This striking tree is an official national emblem of Hong Kong, but it originated in China, as a cross between Bauhinia variegata and B. purpurea. It produces enormous (up to five inches in diameter!), five-petaled flowers. A Hong Kong orchid tree grows just behind Ranger Base at the Safari Park.
Purple Orchid Tree
These are the most common orchid trees in landscaping. They reach 20 to 35 feet tall and wide, and treat viewers to pink or purple flowers that are two to three inches in diameter.
White flowers cover this deciduous orchid tree spring through fall.
Red Orchid Bush
This semi-deciduous shrub grows in full sun, and bears bright red-orange flowers summer and fall. Though called a "bush," it can reach 10 to 15 feet (3 to 5 meters) tall and spreads to 25 feet (nearly 7 meters). At the Safari Park, red orchid bushes adorn the entrance plaza and Safari Base Camp. At the Zoo, look for them on the west side of the Canopy Bridge.
A medium-sized shrub, this Bauhini reaches about 6 feet (2 meters) tall in full sun. Its arching stems bear light green leaves and, in the summer, lovely yellow flowers. You'll find this shrub inside the Safari Park's Hidden Jungle.