barleria prionitis

porcupine flower


Barleria prionitis

L. 1753

pronounced: bar-LEER-ee-uh pry-on-EYE-tiss

(Acanthaceae — the black-eyed Susan family family)


common name: porcupine flower

Barleria is named in honour of Jacques Barrelier (1606-1673), a French Dominican monk who was a physician, botanist, plant collector and author; prionitis is from the Greek πριων (prion), a saw, a jagged row. The plant is a native of India, Sri Lanka and eastern, southern and central Africa, as well as in Indonesia, Malaysia and the Philippines. It grows in thickets in waste places at low altitudes (up to about 600 m in elevation), on roadsides and in dry places in evergreen forests. It forms dense thickets that replace native vegetation and prevent revegetation of native species. These thickets reduce pasture productivity, and restrict access to waterways. In Australia, it has been found around townships in the Northern Territory, especially around Darwin, Berry Springs, Katherine, Mataranka and the Victoria River district, in Queensland around Townsville, and on Boigu Island in the Torres Straits. It has recently been observed in the Kimberley region of Western Australia, and it has now appeared on Magnetic Island, in Alma Bay, with a further serious ourbreak in Nelly Bay. It is classified as a noxious weed. To date there are relatively few areas of infestation, and the plant should be able to be eradicated before it becomes established. Sightings should be promptly reported to the local council for quick control.

This is an erect glabrous evergreen shrub, growing up to about 150 cm tall from a single taproot, with lateral roots branching off in all directions. It usually has a single stem, but may be branched. The stems and branches are stiff and smooth, light brown to light grey in colour.

The leaves are up to 10 cm by 4 cm in size, and elliptical in shape, with a pointed tip. The base of the leaves is armed with 3 – 5 sharp, pale-coloured spines, 1 – 2 cm long. These spines can injure humans and livestock.

The yellow-orange tubular flowers, about 4 cm long, are bunched tightly together at the top of the plant, but they also occur singly at the base of leaves. The stamens protrude from the mouth of the flowers. In northern Australia flowering occurs at the end of the wet and the start of the dry seasons (typically April – May).

The seed capsules dehisce explosively to release the seeds, which can be dispersed by water and in dumped garden waste. The capsules are oval-shaped, 13 – 20 mm long, tapering into a sharp pointed beak about 6 mm long. Each capsule contains two fairly large flat seeds typically 8 mm long by 5 mm wide, covered with matted hairs. One plant can produce hundreds of seeds in a single season. It is not known how long the seeds remain viable in the soil, but it is likely to be for several seasons. They require moisture for germination, and in favourable conditions the seeds germinate fairly soon after they are dropped. Seed spread is usually quicker along paths and roads. The plant can probably reproduce vegetatively as well, and most outbreaks have proved to have been caused by garden escapees. The plants appear to live for about 10 years.

The plant has some beneficial properties that have undoubtedly helped to increase its distribution. It is used as a hedge plant, and has numerous medicinal properties, including the treatment of fever, respiratory diseases, toothache, and joint pains. The plant is gathered from the wild for use in traditional medicine, especially in Ayurvedic medicine. The juice from the leaves is applied to feet to prevent maceration and cracking in the monsoon season. An infusion of the roots and leaves is applied to boils and sores to reduce swelling. The bitter juice of the plant is given as a treatment for catarrh.

Because of its antiseptic properties, extracts of the plant are used in the preparation of herbal cosmetics and hair products to promote skin and scalp health.

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.


Photographed in Alma Bay, 2019

Page last updated 12th August 2019