Euphorbia cyathophora

painted spurge


Euphorbia cyathophora

Murray 1786

pronounced: yoo-FOR-bee-uh ky-uh-THOFF-or-uh

(Euphorbiaceae — the spurge family)


common names: painted spurge, wild poinsettia, fire-on-the-mountain

Euphorbia was named for Euphorbus, a physician in ancient Greece; cyathophora is from two Greek words, κυαθος (kyathos), a ladle or cup, and φορεω (phoreo), to carry, bring. The common name ‘spurge’ derives from the Middle English/Old French espurge (‘to purge’), due to the use of the plant's sap as a purgative.

Another plant from tropical America, this is now naturalized in the southern states of the USA, in Australia and in most of the Pacific islands, where it grows as a weed on roadsides and in waste ground. It is very common on Magnetic Island, often giving a welcome splash of colour in overgrown, weedy areas.

It is an erect herb with green stems to nearly a metre tall. The lower leaves are opposite, the upper ones alternate, the petioles slender and 1 – 4 cm long, the blades mostly panduriform with two or four lobes, those of basal leaves sometimes simply ovate, entire or serrate, 4–7 cm long, 1.5–3 cm wide, the uppermost bracteal leaves with basally red-blotched blades, resembling the cultivated poinsettia. The flowers are greenish or yellowish in colour with one or two small nectaries.

The fruits are dehiscent, a 3-lobed capsule, non-fleshy, 3 – 4 mm long, 4 – 6 mm wide. The plant self-sows readily.

This plant is proving to be a highly invasive weed in parts of Australia, particularly on parts of the northern NSW coast, where it invades the coastal hind-dunes. It is a pest on a number of the Pacific islands, particularly Fiji and Niue. It has even found its way to the Galápagos islands, where it flourishes in the arid lowlands.

dangerous 2As with all Euphorbia, the sap is mildly toxic and astringent. In some areas it has been found that both deer and goats like to graze on the young plants – it can’t be very good for them!


Photographs taken in Picnic Bay 2009
Page last updated 27th December 2018