Bauhinia monandra aka Orchid Tree

Bauhinia monandra is in the pea family, Fabaceae. People call it pink bauhinia or butterfly flower. Kew gives its native range as northern and western Madagascar. Useful Tropical Plants notes past doubts about where it came from. It grows in the tropics, where dry spells mark the seasons. People plant it across the tropics for its flowers.

This evergreen grows as a shrub or a round tree. Its listed garden height is about 20 feet [6 metres]. Wider accounts give a range of 10–49 feet [3–15 metres]. Its trunk can reach about 1.6 feet [0.5 metres] across. It grows fast and keeps its leaves all year. Chicago Botanic Garden says it has a spreading form. Its blooms come in shades of pink and purple. Plants grown from seed first bloom at three to four years old. In the tropics, blooms and seedpods may appear all year. Chicago lists bloom times as January–February and May–June.

Give this tree full sun and rich soil that drains well. It can grow on poorer, drier sites too. Chicago lists medium water needs and USDA zones 10–11. Its flowers suit its use as a specimen tree. Chicago also lists it for streets in towns and cities. Birds and butterflies visit it. Reports say it does not fix nitrogen, unlike many pea-family plants. Treating the hard seed coat before sowing helps seeds sprout. You can nick or soak the coat to help this process.

This tree can spread from gardens and take root on disturbed ground. Birds and other animals eat its seeds and spread them. Floodwater can move seeds to new sites too. This spread means it may become a weed outside planted areas. The supplied sources name no pests or diseases in particular. They note food uses for young leaves and young pods. People cook both parts as vegetables. Seeds have protein and carbohydrates, but some hydrogen cyanide too. These reports do not show that raw seeds are safe.

People use the pods, leaves, roots, and bark in traditional medicine. Reported uses aim to treat fever, bowel problems, and diabetes. These uses do not prove that the treatments work. One study of leaf extract urged care with repeated medicinal use. Pods and seeds yield black and blue dyes. The bark gives fibre for cord. People also burn the hard wood as fuel.