Huernia zebrina
| Light | Bright, indirect light; some direct sun with acclimatisation, but shade from harsh afternoon sun |
|---|---|
| Water | Regularly in the growing season once the mix dries; keep nearly dry and cool in winter |
| Soil | Very free-draining, gritty mineral mix (see Soil and potting mix) |
| Temperature | Keep above about 10 °C; frost-tender, USDA zones 10–11 |
| Propagation | Stem cuttings (very easy); also seed |
| Toxicity | Generally regarded as non-toxic, though the sap may irritate; best kept away from curious pets |
Huernia zebrina is a low-growing, clump-forming stem succulent from southern Africa, prized for its extraordinary star-shaped flowers. Each bloom is a pale yellow to cream star boldly barred with maroon or red "zebra" stripes, and at its centre sits a thick, glossy, raised ring — an annulus — that looks uncannily like a doughnut or a boiled sweet, earning the plant the affectionate common name lifesaver plant. It belongs to the genus Huernia, part of the stapeliad group within the family Apocynaceae.
Description
Huernia zebrina is a small, leafless succulent that grows into low mats or clumps of upright to sprawling stems, each typically only a few centimetres tall. The stems are grey-green, soft-fleshed and angular, usually with about five ribs edged with rows of short, soft, tooth-like tubercles rather than true spines. Like most stapeliads the plant has no leaves; the stems do all the photosynthesis and the water storage.
The flowers are the reason growers seek this species out. They emerge low on the stems, often near the base, as five-lobed stars a few centimetres across. The lobes are pale cream to sulphur-yellow, densely marked with fine transverse bands of dark red to maroon, and the whole surface has a slightly waxy, ridged texture. Rising from the centre is the distinctive raised ring — deeply coloured, shiny and swollen — that gives the flower its "lifesaver" look. As with other stapeliads, the flowers are pollinated by flies and can carry a faint carrion scent, though H. zebrina is far milder in this respect than its larger Stapelia relatives.
Distribution and habitat
The species is native to southern Africa, occurring across parts of South Africa, Namibia, Botswana, Zimbabwe and neighbouring areas. It is a plant of hot, dry, rocky country, where it grows tucked among stones, in rock crevices and beneath the light shade of nurse shrubs and grasses. In these settings the stems are often partly hidden and protected from the fiercest sun, while sharp drainage keeps the roots from ever sitting wet. Several regional forms and subspecies have been described, and stem and flower details vary somewhat across its range.
Cultivation
Huernia zebrina is one of the easier and more rewarding stapeliads for a windowsill or greenhouse, and it flowers freely even as a small plant. Grow it in a very free-draining, gritty mix — a mostly mineral blend suits it well — in a shallow pot that dries out quickly. Give it bright light with some protection from scorching afternoon sun; too little light produces weak, etiolated stems that are reluctant to bloom, while a little gentle sun stress often deepens the stem colour.
Water regularly through the warm growing season, letting the mix dry between drinks, and then keep the plant nearly dry and cool over winter. As with all stapeliads, overwatering and stale, water-retentive compost are the quickest way to lose a plant to rot. See Watering and Repotting for general technique. Clumps are easily divided and grown on, and the species also does well in hanging pots where the stems can trail over the edge.
Propagation
Propagation is very easy from stem cuttings. Detach a healthy stem segment, allow the cut surface to dry and callus for a few days, then set it on or just into a gritty, barely-moist mix; roots form readily in warm conditions. Rooted clumps can also simply be divided at repotting time. The species can be raised from seed as well, though cuttings are so quick and reliable that seed is mostly used by those chasing variation or making crosses. Huernias hybridise readily with one another, so seed from a mixed collection may not come true.
Common problems
- Rot — by far the commonest killer, caused by overwatering, poor drainage or a cold, wet winter; affected stems turn soft, translucent and blacken. Remove healthy tips as cuttings if the base is lost.
- Etiolation — thin, pale, stretched stems and shy flowering indicate too little light.
- Pests — mealybugs hiding between the stems and around the roots are the main nuisance; watch also for aphids on the developing flower buds.
See also
- Huernia — the genus overview
- Stapelia — larger-flowered relatives in the same stapeliad group
- Propagation — cuttings · Soil and potting mix · Watering · Repotting · Pests and diseases