Dwarf pinwheel flower (Tabernaemontana)

This is an ornamental shrub in the genus Tabernaemontana, family Apocynaceae, and a dwarf form of the plant. This page only goes as far as the genus, for the reason below.

The name question. The plant commonly called "ma cha hua" (馬茶花) in Taiwan is given the scientific name Tabernaemontana pandacaqui by the Catalogue of Life in Taiwan, and is naturalised in Taiwan; the name Tabernaemontana divaricata, formerly used in Taiwan, is listed there as a misapplication. On the other hand, Singapore's National Parks Board lists the dwarf form under T. divaricata. Both names are accepted species in global plant checklists, so the sources do not agree on which species this dwarf form belongs to, and this page leaves the question open.

Appearance. Singapore's National Parks Board describes the dwarf form as a low, bushy shrub with glossy green, lance-shaped leaves with a tapering tip, arranged in opposite pairs. The flowers are white, with 5 petals arranged anticlockwise like a pinwheel and a white corolla tube. They are borne in clusters (cymes) at the branch tips, all year round. It is used for hedges, flower beds and containers.

Sap and toxicity. When the plant is injured or broken it exudes a milky white sap. Singapore's National Parks Board marks T. divaricata as toxic if eaten.

The genus name. The genus honours the 16th-century German herbalist Jakob Theodor, whose Latinised surname was Tabernaemontanus.

No species in the genus is listed in the CITES Appendices.