Euphorbia enopla
| Light | Bright light to full sun; benefits from strong light to keep spines colourful and growth compact |
|---|---|
| Water | Moderately in the growing season, letting the mix dry out between waterings; keep dry and cool in winter |
| Soil | Fast-draining mineral-rich mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 9b–11 |
| Propagation | Stem cuttings (allow to callus); seed |
| Toxicity | Toxic — the milky latex is a skin, eye and mucous-membrane irritant (see below) |
Euphorbia enopla is a clustering, green columnar succulent from South Africa, densely armed with slender, showy spines that are actually persistent, hardened flower stalks. Their bright red to reddish colour against the ribbed green stems gives the plant its common name, pincushion euphorbia, and makes it one of the more ornamental of the spiny southern-African euphorbias.
Description
Euphorbia enopla forms upright, cylindrical stems that branch freely from the base to build a dense, many-headed clump over time. Each stem is a rich green, ridged into several prominent ribs, and can reach a few tens of centimetres tall while staying only a couple of centimetres thick.
The plant's most striking feature is its armament. What look like spines are in fact the dried, persistent peduncles — the stalks that carried the flowers — which harden and remain on the plant. They are slender, sharp, and typically red to reddish-brown, standing in neat rows along the rib margins and giving the stems a bristling, pincushion-like look. As with all members of the genus, the true flowers are tiny and are held in specialised cup-like structures called cyathia; in this species the flowering heads sit at the stem tips.
Like other succulent euphorbias, the plant is dioecious, meaning individual plants are either male or female, so seed set requires two flowering plants of opposite sex.
Distribution and habitat
Euphorbia enopla is native to the Eastern Cape of South Africa, where it grows on rocky slopes and in scrubby, well-drained ground within the region's semi-arid karoo and thicket vegetation. In habitat it experiences bright light, sharp drainage, and a pronounced dry season, all of which inform how it should be grown in cultivation.
Like other succulent members of its genus, Euphorbia enopla is listed under CITES Appendix II, which regulates international trade; nursery-grown plants are widely available and straightforward to own and trade.
Cultivation
This is an undemanding and forgiving succulent, well suited to growers who already keep cacti and other stem-succulent euphorbias. Give it the brightest position you can — full sun or very bright light — which keeps the stems compact and the spines well coloured; in weak light the growth stretches and pales. Pot it in a very free-draining, mostly mineral mix.
Water moderately through the warm growing season, always letting the mix dry out before watering again, and then keep the plant dry and cool over winter to prevent rot. As a clumping plant it appreciates being potted on when it fills its container; see Watering and Repotting for general technique.
A word of caution: all euphorbias bleed a milky white latex when cut or bruised, and in this genus it is an irritant. Wear gloves and eye protection when taking cuttings or handling damaged stems, keep the sap away from your eyes, mouth and any broken skin, and wash promptly if it makes contact.
Propagation
The easiest method is by stem cuttings. Remove a stem or side branch, rinse or blot the flow of latex, and let the cut end callus and dry for several days before setting it in a dry, gritty mix to root; keeping cuttings on the dry side until roots form helps prevent rot. Because the plant is dioecious, seed is only an option where both a male and a female plant are in flower together, but seed-grown plants can be raised in the usual way — see Propagation — seed.
Common problems
- Rot — the commonest cause of loss, almost always from overwatering, a slow-draining mix, or wet, cold winter conditions; affected stems soften and discolour.
- Etiolation — too little light makes the stems thin, pale and stretched, and dulls the red of the spines.
- Pests — mealybugs (white fluff tucked between the ribs and at the base) and, in dry stagnant air, spider mites are the usual offenders. See Pests and diseases.
- Irritant sap — not a plant health problem but a grower one: the latex irritates skin, eyes and mucous membranes, so handle with care as noted above.
See also
- Euphorbia — the genus overview
- Propagation — cuttings · Soil and potting mix · Watering · Repotting · Pests and diseases