Crown-of-thorns(Euphorbia milii or Christ Plant) is a species of Euphorbia native to Madagascar.
It is a succulent climbing shrub growing to 1.8 m tall, with densely spiny stems, the straight, slender spines up to 3 cm long, which help it scramble over other plants. The leaves are obovate, up to 3.5 cm long and 1.5 cm broad. The flowers are small, subtended by a pair of conspicuous petal-like bracts, variably red, pink or white, up to 12 mm broad.
It is a shrub of arid regions, belonging to the spurge family, Euphorbiaceae. It is native to Madagascar but is grown extensively as a houseplant. The slender stems are armed with spines, the leaves are dull green and fall off if disturbed, and the flower bracts are a soft salmon-pink with a pale center. The crown-of-thorns is grown as a hedge plant in the tropics, where it may reach a height of 1.2 m (4 ft).