Euphorbia resinifera aka African Spurge

Euphorbia resinifera, or resin spurge, belongs to the spurge family. It comes from Morocco, including slopes of the Atlas Mountains. Growers also call it Moroccan mound or African spurge. Its thick stems look like those of a cactus. This succulent shrub grows slowly into a broad, dense mound. Garden plants reach 1–2 feet [0.3–0.61 metres] tall. Their usual spread is 4–6 feet [1.2–1.83 metres]. LLIFLE reports clumps reaching about 6.6 feet [2 metres] across.

Many upright stems branch to form the mound. Each stem has four sides and a nearly square outline. Their colour ranges from pale green to bluish green. A powdery coating gives some stems a blue cast. Short, sharp spines grow in pairs along the stem edges. The plant has few or no leaves. Its green stems carry out photosynthesis instead. Cut or broken stems release thick, white latex. The species name refers to this resin-like sap.

Small flowers appear along the stem ribs from spring into early summer. Plants seldom flower outside their native range. Each cyathium holds tiny flowers inside a cup-like structure. Pale greenish-yellow flowers sit near yellow-orange glands. These small blooms add little to the plant's bold outline. The fruit is a small capsule. Each cell within it holds one seed.

Give resin spurge sun or some shade and freely draining soil. It tolerates sand, rocky ground, and a wide pH range. It needs little water and withstands drought once grown. From spring through fall, water after the surface inch dries. Cut back watering in winter to prevent wilting without soaking roots. It grows outdoors in USDA zones 9–11. Use it in pots, borders, rock gardens, or dry gardens. It also grows as a houseplant. Deer and rabbits tend to leave it alone.

Pests and diseases seldom cause major trouble. Watch for mealybugs, spider mites, and scale. Too much water can cause root rot. Stem cuttings need a week to dry before planting. All parts are toxic and unsuitable for eating. The latex can inflame skin and blister the mouth. Eye contact can cause lasting damage. Wear gloves and keep children and pets away. Historical uses include purging, inducing vomiting, and treating snakebite. These uses do not make the plant safe.