Euphorbia (Spurges)

Euphorbia (Spurges) is a genus of flowering plant s in family Euphorbiaceae, comprising 2003 species. It is one of the most diverse genera in the plant kingdom, providing a wide range of plant types, from the popular houseplant poinsettia to hardy, evergreen shrubs. The species are primarily found in the tropical and subtropical regions of Africa and the America, but also the temperate zones worldwide. Succulent species originate mostly from Africa, the Americas and Madagascar. The botanical name Euphorbia derives from Euphorbus, a Greek physician of King Juba II of Numidia, while the common name 'spurge' derives from Middle English/Old French espurge (to purge), due to the use of the plant's sap as a purgative.

Euphorbia species are annual, biennial, perennial herbs, shrubs or trees with a caustic, poisonous milky sap (latex). All spurges have unisexual flowers. The flowers are insignificant but usually surrounded by colorful bracts. The bracts are often leaf-like, sometimes brightly colored abd attractive, sometimes reduced to tiny scales. Its fruits are three compartment capsules, sometimes fleshy but almost always ripening to a woody container that splits open. The seeds are 4-angled, oval or spherical, and in some species have a caruncle.

One of the best perennials is Euphorbia griffithii, 90 x 60 cm, which grows in sun or partial shade. The dark green leaves have red ribs and in summer, red, yellow or orange flowerheads are produced.

Euphorbia pulcherrima, commonly known as Poinsettia, is a species indigenous to Mexico. The name 'Poinsettia' is named after the first United States Minister to Mexico, Joel Roberts Poinsett, who introduced the plant into the US in 1828. Euphorbia pulcherrima, 0.6 x 4 m, is a shrub or small tree. It bears dark green dentate leaves that are 7 - 16 cm long. The colored bracts are actually leaves, which come in the common flaming red, but can be orange, pale green, cream, pink, white, or marbled. Many people often think the bracts are the flower petals of the plant. In fact, the flowers are grouped within the small yellow structures found in the center of each leaf bunch, and they are called cyathia.

Euphorbia albomarginata (Rattlesnale weed, whitemargin sandmat) is a low-growing species, native to desert and chaparral habitats of southwestern North America, from southern California to Texas. It is a common ground cover plant, 1 - 2 cm high, often growing closely and forming mats of vegetation. The flowers are tiny and are edged in white, with a purplish center. It can be found in open field, on roadsides, or anywhere where the ground is undisturbed. Like most Spurges, Euphorbia albomarginata secretes an acrid, milkysap containing alkaloids poisoning to human.

Euphorbia species come in wide range of size and habit, and are known for their evergreen foliage and their use as groundcovers. Euphorbia grows well in sun or shade and well-drained soil. Propagation is by seed ins pring; divide in early spring ; and basal cuttings in spring. Aphids and grey mould are pest and disease that affect the plant.

Euphorbia characias
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