Bauhinia monandra

pink orchid tree

 

Bauhinia monandra

Kurz 1873

pronounced: bow-HIN-ee-uh mon-AND-ruh

(Fabaceae — the pea family)

subfamily: Caesalpinioideae - the cassia subgamily

 

common names: pink orchid tree, Napoleon's plume

Bauhinia was named for the Bauhin brothers, 16th century Swiss botanists; monandra is from the Greek μονος (monos), alone, and ανδρος (andros), of a man – only one man, i.e. only one anther.

A native of Burma, this tree has been planted and has escaped or naturalized itself throughout the East Indies from Cuba and Jamaica to Barbados and Trinidad, to say nothing of Magnetic Island! It has been planted as an ornamental in Puerto Rica, but can be found naturalized in thickets, along roadsides as well as river banks in the coastal, limestone and lower mountain regions. After being cultivated in southern Florida and the deep south of Texas, it is a naturalized plant in these states as well. There are many of these trees on Magnetic Island, in gardens and on road verges.

This is a small, fast-growing, evergreen tree or shrub that commonly reaches 3–15 m in height. Its smooth grey bark can become scaly and reddish brown on older trees. The leaves are shaped like butterfly wings, rounded, and split from a third to a half of their length, forming two equal lobes. They are dissected by 11 or 13 main veins. The petioles extend into short awns between the leaf lobes.

The large 5-petaled orchid-like flowers occur in short racemes; they start out a pale yellow, but turn to pink the next day, and the centre petal is streaked with magenta. The flowers range from 6–10 cm in diameter, have only one fertile stamen per flower, and a calyx splitting along one side. The flowering season is long, as much as 9 months in a good year.

The fruits are dark, dehiscent pods, about 2.5 cm wide and 15 – 30 cm long, pointed at the apex, and containing about 20 seeds. While still on the tree, the pods split open with force and a loud bang, twisting into a spiral and scattering the seeds. The black seeds are elliptic, flat, and about 1 cm long.

In Brazil an extract of the leaves is used to treat diabetes. The wood is used for firewood in Puerto Rico and for fences in Jamaica. The seeds are a useful source of vitamin A. The plant is attractive to bees and butterflies, as well as nectar-eating birds, and the Castor or Croton caterpillar Achaea janata has been found feeding on members of the Bauhinea genus.

In some places this small tree is potted, and used as an indoors or patio plant. For this, it needs bright light, almost any soil, good food but low water.

Propagation is from stem cuttings, either softwood or semi-hardwood, or from seed. If collecting seed, the pods should be allowed to dry on the plant, and removed just before you think they are going to dehisce. The pods are then broken open to collect the seeds, which should be germinated as soon as possible – they do not store well.

 

Information about medicinal qualities of plants, or about their use as medicines, is for interest only, and is not intended to be used as a guide for the treatment of medical conditions.

 

Photographs taken in Picnic Bay 2009, 2013, 2017
Page last updated 19th October 2018