Oldenlandia corymbosa

diamond flower


Oldenlandia corymbosa

L. 1753

pronounced: ole-den-LAN-dee-uh kor-rim-BOW-suh

(Rubiaceae — the gardenia family)


common name: diamond flower

native 4Oldenlandia was named by Linnaeus for Henrik Bernard Oldenland (c.1663-c.1697) German-born South African physician and botanist; corymbosa is from the Greek κορυμβος (korymbos), a cluster of fruit or flowers: full of corymbs.

This little pan-tropical and pan-subtropical plant is usually found as a garden weed, but in south-east Asia is an important medicinal plant. In Australia it is found in the Kimberleys, in the north of the Northern Territory, in the Torres Strait Islands, on Cape York Peninsula, down the eastern coastal and near-coastal regions of Queensland, and occasionally on the NSW coast.

The plant is found in sunny, not too wet sites, especially on hard or stony soils on roadsides, or by the bases of walls, or anywhere in gardens, especially as a weed of potted plants.

It is an annual erect or prostrate herb that grows to about 50 cm, with fibrous white or brown roots. The stems are quadrangular, solid and glabrous. Stipules are present, laciniate.

The leaves are simple, not lobed or divided; they are entire, opposite, stalked, and linear, lanceolate or narrowly elliptic in shape, glabrous on both surfaces; the apex and base is acute, and the midrib is very prominent. Leaves measure 1 – 3.5 cm by 1.5 – 7 mm.

The flowers are bisexual, sometimes solitary but usually 2 – 8 grouped together into an axillary cyme, with a corolla tube about 2 mm long, and 4 white, or occasionally faintly pinkish-purplish, petals, on slender peduncles 4 – 8 mm long; the pedicels are half as long or less. The stamens are inserted just above the base of the tube.

The fruit is a capsule, about 2 by 2 mm in size, shaped like a top, opening with apical slits, and slightly laterally compressed. They do not protrude beyond the short, acuminate calyx lobes. Reproduction is by seeds.

The plant is edible, and a rich source of vitamin C. In the folk medicine of various south-east Asian countries, a decoction of the whole plant is used to treat fevers and stomach ache. It is both taken internally and applied to the skin to treat heat eruptions. In Martinique, a tincture of the roots is used as a vermifuge. In India, juice from the plant is mixed with sugar and milk and used to treat indigestion; the plant is also used to treat jaundice and liver problems, giddiness, flatulence, colic, constipation, bronchitis, and even leprosy. In the Congo, it is used to facilitate childbirth. In Chinese medicine, it is used to treat viral infections, cancer, acne, boils, appendicitis, hepatitis, eye problems and bleeding. In various places it is used as a mouthwash for toothache.

For these medicinal uses, the plant is seldom cultivated, but harvested from the wild.


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 2015
Page last updated 12th February 2019