Pachyphytum oviferum
| Light | Bright light; some direct sun to keep leaves compact and colourful, with shade from the harshest midday sun |
|---|---|
| Water | Soak-and-dry; water thoroughly then let the mix dry out completely, much less in winter |
| Soil | Fast-draining, gritty mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; happiest in USDA zones 9b–11 |
| Propagation | Leaf and stem cuttings; offsets; seed |
| Toxicity | Generally regarded as non-toxic to cats and dogs |
Pachyphytum oviferum, widely known as moonstones or the sugaralmond plant, is a low-growing Mexican succulent prized for its plump, egg-shaped leaves. Each leaf is heavily dusted in a chalky white farina (epicuticular wax) that softens its colour to a pastel blue, lavender or pink and gives the whole rosette the look of a cluster of sugared almonds or smooth river pebbles. It belongs to the genus Pachyphytum in the family Crassulaceae.
Description
Pachyphytum oviferum forms loose rosettes of thick, rounded leaves on short stems that lengthen and sprawl with age, often trailing or leaning as the plant matures. Individual leaves are famously fat and egg-like — 2–4 cm long — and coated in a dense white farina that rubs off easily where the leaf is touched, leaving a fingerprint. Beneath that waxy bloom the leaf colour ranges from pale bluish-green to a soft lilac or peachy pink, deepening (or "blushing") under bright light and cooler temperatures.
In late winter and spring the plant sends up arching flower stalks bearing nodding, bell-shaped blooms in shades of red and greenish-white, partly hidden by protective bracts. As with most Crassulaceae, the flowers are attractive but secondary to the year-round appeal of the foliage.
Distribution and habitat
The species is native to Mexico, where it grows on rocky slopes and cliff faces in the state of San Luis Potosí. In habitat it roots in gritty, sharply drained ground and receives strong sun, seasonal rains and long dry spells — conditions worth keeping in mind when growing it. The thick, farina-coated leaves are adaptations to this bright, arid environment, storing water and reflecting excess light.
Cultivation
Moonstones are a rewarding, beginner-friendly succulent provided their roots are never left wet. Grow them in a very free-draining, mostly mineral mix and water using the soak-and-dry method: drench the pot, then wait until the soil has dried out completely before watering again. Cut back sharply in winter, when the plant is semi-dormant, as cold, damp compost is the quickest route to rot.
Give the plant as much bright light as you can — several hours of gentle direct sun encourages compact rosettes and the best pastel blush. In too little light the stems stretch (etiolate) and the leaves space out and pale. A key point of care: the powdery white farina is delicate and does not regrow once rubbed off, so handle plants by the stem or pot rather than the leaves, and avoid overhead watering that can wash the bloom away and mark the foliage. See Watering and Repotting for general technique.
Propagation
Pachyphytum oviferum is easily propagated by cuttings and leaves. A whole leaf, cleanly detached at the base, will often callus and sprout roots and a tiny new plantlet; stem cuttings root readily the same way after a few days' drying. Mature plants also form offsets that can be separated once rooted. Seed is possible but slower and mainly of interest for hybridising. Let all cut or detached material callus in a dry, shaded spot before setting it on barely moist, gritty mix.
Common problems
- Rot — the most frequent cause of loss, almost always from overwatering, a slow-draining mix, or water sitting in the rosette; affected leaves and stems turn soft and translucent.
- Etiolation — insufficient light stretches the stem and spaces out the leaves, spoiling the compact rosette form.
- Lost farina — the chalky bloom is easily rubbed or washed off, leaving permanent shiny marks; it will not grow back on that leaf.
- Pests — mealybugs (white fluff tucked between the leaves) and the occasional aphid on flower stalks are the usual offenders. See Pests and diseases.
See also
- Pachyphytum — the genus overview
- Graptopetalum and ×Pachyveria — a related genus and the Pachyphytum × Echeveria hybrid, both often confused with moonstones
- Propagation — cuttings · Propagation — offsets · Soil and potting mix · Watering