Euphorbia milii (Crown of thorns)

Euphorbia milii, commonly known as Crown of Thorns or Christ Plant, is a spiny evergreen to semi-deciduous succulent shrub in the Euphorbiaceae family native to Madagascar. It develops thick, branching grayish stems armed with prominent sharp spines and typically grows 2-6 feet (0.6-1.8 m) tall, depending on the form and growing conditions. The small true flowers are surrounded by showy, long-lasting bracts, traditionally bright red but ranging through pink, yellow, orange, cream, white, and numerous intermediate shades in modern cultivars and hybrids. Under warm, bright conditions, plants can flower almost continuously throughout the year.

Euphorbia milii grows best in full sun to bright filtered light and sharply drained soil, with moderate watering followed by some drying of the soil. Established plants tolerate heat and drought well, while excessive moisture can cause root and stem rot. Numerous cultivars and complex hybrids have been developed, including large-flowered Thai hybrids with exceptionally broad, colorful bracts and more compact forms suited to containers. Hardy in USDA Zones 9-11, plants should be protected from frost and prolonged cold and are widely grown as houseplants in cooler climates. Broken stems and leaves release the characteristic white Euphorbia latex, which is irritating to skin and eyes and toxic if ingested, while the sharp spines also require care when handling the plant. A single complete collection of cultivars wouldn't exist because too many hybrids were produced. See Thai Euphorbias - exotic milti-colored.

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