The genus Euphorbia is one of the giants of the plant world, with roughly 2 000 species ranging from tiny annual “weeds” to sizeable shrubs and trees.

Many of the most charismatic members are the succulent spurges of Africa, where thickened, photosynthetic stems and water-storing roots allow them to thrive in semi-arid Karoo, savanna and bushveld landscapes. At a glance many of these plants are easily mistaken for cacti, yet they belong to a completely different family and are united instead by their unique flower structure, the cyathium – a tiny cup that holds the actual male and female flowers and nectar glands.

Almost all Euphorbia species exude a milky white latex when damaged. This sap has helped the genus to succeed as it seals wounds and has antifungal and antibacterial properties, but it is also irritating and sometimes highly toxic to skin, eyes and mucous membranes, so care and gloves are strongly recommended when pruning or transplanting.

For South African gardeners and collectors, the succulent euphorbias offer tough, water-wise structure for rock gardens, containers and xeriscapes. Their sculptural stems, intricate spination and neat clusters of yellowish cyathia are especially striking in late spring and summer. The species below are all South African endemics with fascinating forms and restricted natural distributions, making them rewarding subjects to grow from seed and a meaningful contribution to ex-situ conservation when sourced responsibly.

Euphorbia clivicola

This compact, mat-forming succulent spurge is instantly recognisable by its dense cushion of short, four-angled branches studded with paired spines. Stems arise from a thickened underground stem and rootstock and are typically 3–6 cm long, producing tight clumps that sit low against the stony ground.

The fresh growth shows a bright, slightly glaucous green, while older stems can take on warmer, olive tones.

Euphorbia clivicola is a South African endemic, naturally restricted to rocky slopes and low cliffs on the Polokwane Plateau in Limpopo Province, near Polokwane and Mokopane.

Plants grow in shallow soils over quartzite and other hard rocks in open bushveld, where they experience hot, dry summers and cold, often frosty winters. This tiny range, together with ongoing habitat loss and disturbance, has led to the species being assessed as Critically Endangered.

In the growing season this species produces charming clusters of small yellow to yellow-green cyathia at the tips of new growth, bringing a subtle glow to the mat of spiny stems. Flowering is mainly in spring, often triggered by the first sustained warmth and moisture of the season.

In cultivation, E. clivicola thrives in shallow containers or rock-garden pockets with a very gritty, well-drained medium and good light, yet appreciates a little protection from the fiercest midday sun in the Lowveld and central Karoo. Seed-grown plants are ideal for collectors who appreciate unusual dwarf euphorbias: they stay compact, develop tight cushions over time, and reward patient growers with an ever-more intricate mound of angular stems and spines.