pronounced: kler-oh-DEN-drum tom-SOH-nee-ay
Clerodendrum comes from two Greek words, κληρος (kléros), fate, or chance, and δενδρον (dendron), a tree. Thomsoniae was named for the Reverend William Cooper Thomson. I have not been able to find out the actual years of his birth and death, but they are pre-1820 to post-1880. He was a missionary and a physician in Nigeria for the Church Missionary Society from 1838 to 1840, and possibly longer. This plant was very popular in the mid-19th century (when it was known as ‘beauty bush’), then went out of favour, and has now staged a come-back.
The species is native to tropical West Africa. It is an evergreen, sprawling, vine-like shrub, whose stems can be anything up to 5 m long; they can climb without tendrils, suckers or root hairs, by twining through and around a support.
The ovate to oblong leaves are large, up to about 18 cm in length, and are arranged opposite to each other along the stems. They are glabrous, entire, and have strong veins.
Through the summer, panicles of between 5 and 20 showy red and white flowers are produced. The individual flowers are about 2.5 cm in diameter, bell-shaped with white (occasionally pale purple) 5-lobed calyces and crimson red petals. As is typical of the Clerodendra, the flowers have 4 stamens and a style that extend out beyond the petals. Long after the red petals have disappeared, the white calyces remain, as can be seen from the photograph of a plant that has almost finished its flowering season.
Inedible black and orange-red berries are produced, with black seeds.
In some regions the plant has escaped from cultivation and become naturalized.
This is an excellent plant for a tub or a hanging basket. It can be kept pruned into a shrub, or given support and be allowed to scramble. It does not spread as much as some (e.g. Clerodendrum splendens), so it is a good choice for a restricted site; it is not such a good plant if it is desired to cover a fence or an arbor. It needs to be kept moist but not exceedingly wet, with plenty of good light. It seems to give best results with morning sun and afternoon shade. Since it blooms on new growth, it should be cut back after blooming. It is usually propagated by cuttings, but it is possible to grow it from seed, or by layering, or by replanting suckers. Quickest results can be obtained from root cuttings taken in winter.