Conophytum obcordellum
| Light | Bright, filtered light; strong light brings out the top patterning, but shade from harsh midday summer sun |
|---|---|
| Water | Autumn to spring only; keep bone-dry through the summer dormancy (see Watering) |
| Soil | Very free-draining mineral mix (see Soil and potting mix) |
| Temperature | Cool grower; keep frost-free, roughly USDA zones 9b–11 |
| Propagation | Seed and division of clumps (see Propagation — seed, Propagation — offsets) |
| Toxicity | Not known to be toxic to cats or dogs |
Conophytum obcordellum is a small, flat-topped "cono" from South Africa, prized for the intricate reddish to purplish dotted patterning on the tops of its paired-leaf bodies, and for its sweetly night-scented flowers. It is a variable species that encompasses a whole cluster of collectible named forms and subspecies, making it a favourite among Conophytum enthusiasts.
Description
Like all Conophytum, C. obcordellum consists of a pair of highly fused, fleshy leaves united into a single obconic to kidney-shaped body only a couple of centimetres across. The top is flat or slightly domed, split by a small mouth-like fissure, and is decorated with fine dotted lines, speckles and reddish markings, some of them translucent — a pattern that varies enormously from plant to plant and is much of the reason growers collect the species. Bodies cluster over time into low, tight mats.
Each growing season the old leaf pair dries to a papery sheath and a fresh body emerges from within it. Flowers appear in autumn: small, many-petalled and usually creamy white (sometimes pink-tinged), and — unusually for the genus — they open in the evening and release a strong sweet fragrance to attract moth pollinators.
Distribution and habitat
Conophytum obcordellum is native to the winter-rainfall region of the Western and Northern Cape of South Africa, where it grows on rocky sandstone outcrops, in crevices and in the shelter of low shrubs, often among lichens and mosses. Plants often sit wedged into cracks or nestled among stones that give them some shade and run-off. The climate there is the reverse of most temperate gardens: mild, moist winters and hot, bone-dry summers, and the plant's growth cycle is tuned to match.
Cultivation
The single most important thing to understand about Conophytum obcordellum is its reversed, winter-growing rhythm. It is dormant through the heat of summer and does almost all of its growing, flowering and drinking in the cooler months. Water from autumn through to spring, letting the mineral mix dry between waterings, then withhold water almost entirely through summer while the plant rests inside its papery sheaths. A little air movement and shade in the hottest part of summer helps prevent cooking.
Grow it in a shallow pot in bright, filtered light — enough to keep the bodies compact and to develop the top patterning, but with protection from the fiercest midday sun. Because the roots resent staying wet, a gritty, sharply drained substrate is essential. See Watering and Repotting for general technique.
Propagation
Established clumps can be divided: lift a cluster during the dormant-to-active transition in late summer or early autumn, tease apart rooted heads, and let any cuts dry before potting so they can root as the growing season begins. See Propagation — offsets for the method. The species also comes readily from seed, sown in autumn onto a fine mineral surface kept lightly humid; seed is the usual way to raise the many forms and to preserve genetic variety. See Propagation — seed for a full walkthrough.
Cultivars
C. obcordellum is a notably variable species, and a number of its wild forms and subspecies have long been grown and traded under their own names for particular top patterns and colours — including the well-known form picturatum and subspecies ceresianum, valued for their distinctive top markings. Because the boundaries between these forms are blurry and have been reshuffled by botanists over the years, collectors often value plants by their appearance and provenance as much as by a formal name.
Common problems
- Rot — the usual killer, almost always from watering during the summer dormancy or from a mix that holds too much moisture; bodies turn soft and translucent-brown.
- Failure to shed / stacking — too much water at the wrong time can leave old sheaths clinging and bodies stacking untidily instead of renewing cleanly.
- Etiolation — too little light makes bodies swell, pale and lose their pattern and compact form.
- Pests — mealybugs (including root mealybugs) and the occasional spider mite; check inside sheaths and around the roots. See Pests and diseases.
See also
- Conophytum — the genus overview
- Soil and potting mix · Watering · Repotting · Propagation — seed · Propagation — offsets · Pests and diseases