Diverse genus of about 2,000 species, ranging from small flowery annuals to sculptural trees. The flower is technically a cyathium, consisting of fused bracts that form a cup around the much-reduced true flowers. Cyathia may appear singly or in clusters. In some cases, as with poinsettia (E. pulcherrima), additional bracts below provide most of the color. The fruit is usually a dry capsule that releases seeds explosively, shooting them up to several feet away. Many euphorbias are succulents; these often mimic cacti in appearance and are as diverse in form and size.
All euphorbias have milky white sap that is irritating on contact or toxic if ingested (degree of irritation or toxicity varies, depending on the species). Before using cut flowers in arrangements, dip stems in boiling water or hold in a flame for a few seconds to prevent sap bleed. All need well-drained soil.
Mediterranean native forms a 3–5-ft.-wide clump of stems that angle outward, then rise up to 2 ft. high. Fleshy gray-green leaves to 1 1/2 in. long are narrow and pointed, their bases set tightly against stems. Broad, domed flower clusters in late winter or early spring are chartreuse-yellow fading to pinkish. After seeds ripen, stems die back and should be removed; new stems take their place. Reseeds in mildest-winter areas, but not enough to become a pest. Showy display plant in borders, rock gardens, and containers. Full sun. Tolerates drought.