Dinteranthus wilmotianus
| Light | Very bright light with several hours of direct sun; a sunny windowsill or bright greenhouse |
|---|---|
| Water | Extremely sparingly; a fully mineral mix that dries fast, with a long dry rest (see Watering) |
| Soil | Sharp, almost purely mineral grit (see Soil and potting mix) |
| Temperature | Keep dry and frost-free in winter; roughly USDA zones 9b–11 |
| Propagation | Seed (see Propagation — seed) |
| Toxicity | Not known to be toxic to cats or dogs |
Dinteranthus wilmotianus is a small, stemless mesemb from the arid interior of South Africa that grows as one or two pairs of thick, keeled leaves the colour of pale grey stone. Each smooth, chalky leaf pair is finely speckled with darker dots and split by a shallow fissure from which a bright yellow, daisy-like flower emerges, and the whole plant sits flush with the ground so that it mimics the quartz pebbles around it. It belongs to the small genus Dinteranthus, a close relative of the living stones (Lithops) and one of the more challenging groups for beginners to keep alive.
Description
Dinteranthus wilmotianus forms a very compact, almost buried body made up of a single pair — occasionally two pairs — of fused, boat-shaped leaves. The leaves are markedly keeled beneath, giving each pair an angular, wedge-like profile, and their surface is a soft, uniform grey to greyish-white overlaid with a fine dusting of tiny darker speckles. Unlike Lithops, the plant has no translucent leaf-top "window" and no obvious island markings; the camouflage comes instead from its overall pebble colour, low keeled shape and speckling.
The plant lacks a true stem and, with its tiny body, depends heavily on a shallow root system. Flowers appear from the central fissure in late summer and autumn: glossy yellow, many-petalled and opening in the afternoon sun, they are large in proportion to the tiny body. After flowering a dry capsule forms that opens to release seed when wetted by rain.
Distribution and habitat
The species is native to the dry interior of South Africa, in the arid, winter-cool, summer-rainfall parts of the Northern Cape. It grows in open, exposed quartz and gravel fields, wedged among light-coloured pebbles that it closely resembles. Rainfall there is low and unreliable, drainage is near-perfect, and the plants endure intense sun, hot days and cold nights — conditions that shape how they must be grown in cultivation.
Cultivation
Dinteranthus has a reputation as one of the trickiest mesembs, and D. wilmotianus is no exception; the single most common cause of loss is watering too much or at the wrong time. Grow it in a very small pot in a sharp, almost entirely mineral mix — think pumice, grit and coarse sand with only a trace of organics — so that water races through and the roots never sit damp. Give it the brightest position you can, with several hours of direct sun, as too little light makes the body swell, pale and lose its tight stony form.
Water is best thought of as an occasional event rather than a routine. The plants take up most moisture in late summer and autumn as they grow and flower; through the cold, low-light months they should be kept essentially bone dry, and even in the growing season a light soaking followed by a long drying-out is far safer than frequent sips. Because the tiny body stores so little water, a rotted root system is often fatal, so err firmly on the side of underwatering. See Watering and Repotting for general technique, and handle repotting only when the plant is in active growth.
Propagation
Seed is the standard and most reliable method. Sow the fine seed onto a firmed, gritty mineral surface, keep it lightly moist and warm until germination, then ease the seedlings toward the same lean, dry regime as adults as they establish. Seedlings are tiny and slow, and damping-off from overwatering is the main early hazard. The plants rarely branch or offset, so vegetative propagation is uncommon. See Propagation — seed for a full walkthrough.
Common problems
- Rot — by far the leading killer, caused by overwatering, a mix that holds moisture, or watering during winter dormancy; the body goes soft, translucent and collapses.
- Etiolation — too little light makes the leaf pair bloat upward, turn greener and lose its low, keeled, pebble-like shape.
- Split or scarred bodies — sudden heavy watering after a long dry spell can cause the leaves to swell and crack.
- Pests — mealybugs (white fluff in the fissure and around the roots) and root mealybugs are the usual culprits; see Pests and diseases.
See also
- Dinteranthus — the genus overview
- Lithops — the closely related living stones
- Soil and potting mix · Watering · Propagation — seed · Repotting · Pests and diseases