Adromischus
Adromischus is a small genus of dwarf, slow-growing succulents in the stonecrop family Crassulaceae, native to South Africa and Namibia. The genus is treasured by collectors for its endlessly varied, chunky leaves — often thickly patterned, mottled, spotted or bumpy — and for how obligingly a single dropped leaf will root and grow into a new plant. The name comes from the Greek for "thick stem," a nod to the short, often woody stems on which the fat leaves are crowded.
Description
Adromischus are compact plants, most no more than a hand's-width across, forming small clumps of short stems densely set with fleshy leaves. It is the leaves that make the genus: they range from flattened paddles to plump cigars and near-spheres, and their surfaces may be smooth, waxy, warty or velvety. Many carry striking maroon or purple mottling over a grey-green base, a pattern that intensifies in bright light. Older stems frequently develop a coat of rusty brown aerial roots and become gently woody at the base.
The flowers are modest compared with the foliage. Slender upright spikes rise from the crown bearing small tubular blooms in whitish, green or pinkish tones, with the petal tips flared back. Most growers keep the genus for the leaves rather than the flowers.
Distribution
The genus is centred on the winter-rainfall regions of the western and southern Cape of South Africa, extending into Namibia. Plants grow in rocky, arid habitats — wedged into cracks, gravel pockets and the shade of larger shrubs — where they endure long dry spells and rely on their swollen leaves for water storage. Because many species come from winter-rainfall areas, they can be inclined to grow in the cooler months and rest through the heat of summer, though behaviour varies by species and climate.
Notable species
- Adromischus cooperi — plump, wavy-edged spotted leaves; one of the most widely grown.
- Adromischus cristatus — the "crinkle-leaf plant," with fan-shaped leaves fringed by a wavy crest and a stem furred in reddish aerial roots.
- Adromischus marianae — a hugely variable species prized for its warty, richly coloured leaf forms (including the sought-after 'Herrei' and 'Alveolatus' types).
- Adromischus maculatus — the "calico hearts," with flat leaves heavily spotted in chocolate-purple.
- Adromischus filicaulis — slender-stemmed, with narrow speckled leaves.
Cultivation
Adromischus are among the easier small succulents to keep, asking only for sharp drainage and restraint with the watering can. Grow them in a gritty, fast-draining, mostly mineral mix in a snug pot, and give them bright light — plenty of sun brings out the leaf colours and keeps growth tight, while too little light makes stems stretch and leaves pale.
Water thoroughly once the soil has dried out, then let it dry again; err on the dry side, since the fat leaves hold ample reserves and rot follows overwatering quickly. Pay attention to each species' growing rhythm — the many winter-growers appreciate more water in the cooler months and a drier rest in high summer. Protect all species from frost. A drawback worth knowing: leaves can drop at the slightest knock, so handle plants gently. See Watering and Repotting for general technique.
Propagation
This is the genus's party trick. A single healthy leaf, gently detached and laid or barely set on the surface of dry, gritty mix, will usually root and, in time, push up a tiny plantlet from its base. Let the leaf callus for a day or two first, keep it warm and only lightly moist, and be patient. Stem cuttings and division of clumps also work well. Seed is possible but slow and mostly the domain of specialists chasing new leaf forms. See Propagation — leaf, Propagation — cuttings and Propagation — offsets for full walkthroughs.
Hobby and cultivar notes
Much of the fascination in Adromischus lies in variation within a species: growers collect distinct leaf forms — differing in shape, warting and colour — of variable species like A. marianae, many circulating under form or locality names rather than formal cultivar names. Because the plants are small, slow and undemanding of space, a sizeable collection fits on a single sunny windowsill or shelf, which has made the genus a long-standing favourite among succulent enthusiasts.
See also
- Crassulaceae — the stonecrop family
- Soil and potting mix · Watering · Propagation — leaf · Propagation — cuttings · Repotting · Pests and diseases