Bauhinia is a plant genus that is part of the Fabaceae family. It contains about 570 species of shrubs or trees that are native to tropical and warm temperate regions around the world. Most of the species bloom with orchid-like flowers that have five irregularly shaped petals. They make excellent container plants. Some problems commonly encountered with this genus include insect damage and fungal diseases.
The Bauhinia genus is named after John and Caspar Bauhin, who were Swiss herbalists. Most of the plants in this genus are commonly called mountain ebony trees or orchid trees. Some species have variations on the common names. For example, Bauhinia lunarioides is referred to as the anacacho orchid tree, and Bauhinia variegata is sometimes called the purple orchid tree.
This genus contains plants from around the world. Bauhinia variegata is native to the tropical forests of southeastern Asia. Bauhinia lunarioides is found in the canyons and limestone hills from central Texas down to northeastern Mexico. Bauhinia seminarioi is only found in the subtropical dry forests of Ecuador.
The orchid-like flowers that bloom from shrubs in this genus stand out in most gardens. Depending on the species, the flowers are red, orange, white, pink, or purplish-blue. Some species produce fragrant flowers, such as B. variegata, which has a sweet scent.
Most species in this genus have foliage that is comprised of dark green leaves that are two-lobed. Some species, such as B. variegata, have heart-shaped leaves. Most species are deciduous, so the leaves will fall off in the autumn.
B. variegata reaches 39 feet (12 m) in height and spreads about 26 feet (8 m) when grown under proper conditions. It generally requires well-draining, loamy soil to grow well. Usually, this species can tolerate both acidic and alkaline conditions. It should be planted in an area that is exposed to direct sunlight and is somewhat sheltered from the wind. This species is a tropical plant and can't tolerate frost.
Most species in this genus are susceptible to infestation by whiteflies, aphids, and spider mites. These insects will feed on the leaves and stems of the shrubs. Whiteflies and aphids leave behind a sticky residue which attracts fungal spores. Spider mites produce webbing that is noticeable at the joint where the leaf and stem meet. Washing the foliage with an insecticidal soap usually removes most of the insects, but if the infestation returns, a chemical pesticide may be required to eliminate the insects.