Cyphostemma
Cyphostemma is a genus of pachycaul, caudiciform succulents in the grape family Vitaceae, found chiefly across mainland Africa, the Arabian Peninsula and Madagascar. Once lumped into the sprawling genus Cissus, these are the swollen-stemmed relatives of the grapevine, grown by succulent enthusiasts for their fat bottle-shaped trunks, papery peeling bark and boldly sculptural presence. The best-known species in cultivation is Cyphostemma juttae, often sold simply as the "wild grape" or "tree grape".
Description
Most collectable Cyphostemma share a distinctive silhouette: a stout, water-storing trunk or caudex that tapers upward like a bottle or a small baobab, topped in the growing season by a crown of large, fleshy, often blue-green leaves. The leaves are typically trifoliate or lobed — a clear nod to the plant's grape-family ancestry — and many are covered in a waxy bloom or fine hairs. Bark on mature plants peels away in thin, translucent yellowish sheets, revealing smooth green tissue beneath and giving old specimens a wonderfully weathered look.
These are strongly deciduous plants. In habitat and in cultivation they drop their leaves and rest through the dry season, standing as bare, sculptural trunks for months at a time. Small greenish flowers are borne in branched clusters and, in female plants, give way to grape-like berries that ripen red to purple. The fruits of most species are not edible and can be irritating, so they are best admired rather than sampled.
Distribution
The genus is centred on Africa, with a strong concentration of caudiciform species in the arid southwest — Namibia, Angola and South Africa — where the celebrated C. juttae and C. bainesii grow among rocks and thornscrub. Other species range across tropical and eastern Africa, up into the Arabian Peninsula, and out to Madagascar, which hosts its own distinctive endemic species. Habitats vary from seasonally dry woodland to exposed rocky slopes, but the succulent, hobby-favoured species are overwhelmingly plants of hot, seasonally arid country that endure long dry rests.
Notable species
- Cyphostemma juttae — the classic "wild grape"; a stout grey-green bottle trunk with peeling bark and broad toothed leaves, the entry point for most collectors.
- Cyphostemma bainesii — an accepted species so close in appearance to C. juttae that plants are frequently traded under the wrong name; without leaves it is hard to tell from its swollen-trunked relatives.
- Cyphostemma currorii — a larger, tree-forming species (the "kobas" or "butter tree") reaching considerable size in habitat.
- Cyphostemma cirrhosum — a climbing, tendril-bearing species that shows off the genus's vine heritage more openly.
- Cyphostemma laza — a Madagascan species prized for its thick caudex and ornamental foliage.
Cultivation
Cyphostemma are rewarding, forgiving caudiciforms once you respect their seasonal rhythm. Grow them in bright light — full sun suits established plants and keeps the trunk stocky and the leaves compact — in a very free-draining, mostly mineral mix. During the warm growing season, when the plant is in full leaf, water generously and let the mix approach dryness between soakings; the swollen trunk stores plenty of reserve, so err on the dry side rather than the wet.
The critical rule is the winter rest. As temperatures drop and the leaves yellow and fall, cut water back sharply and keep the plant nearly bone dry until growth resumes in spring. Wet, cold roots are the quickest way to rot a caudex. Keep plants above freezing (roughly USDA zones 10–11); they are not frost-hardy. A snug pot and occasional repotting into fresh gritty mix will keep a specimen healthy for decades, and the caudex thickens most impressively when the plant is grown hard in strong light. See Watering for general technique.
Propagation
Seed is the standard and most reliable method, and the way to obtain a plant with a naturally swollen, well-proportioned trunk. Sow fresh seed on a warm, mineral surface and keep it lightly moist until germination; seedlings develop a fattened base surprisingly early. Cuttings will sometimes root, but stem-grown plants tend to lack the fat basal caudex that makes the genus so desirable, so most growers stick with seed. See Propagation — seed and Propagation — cuttings for full walkthroughs.
Hobby notes
For collectors, Cyphostemma offers a lot of drama for little fuss: a bare, sculptural winter trunk followed by a lush flush of oversized leaves in summer. C. juttae and C. bainesii are so similar that plants are frequently sold under the wrong name — if the exact identity matters to you, buy from a specialist. There are few named cultivars; the genus is grown for the natural character of individual seed-raised plants rather than for selected forms. Note that the sap and fruit of many species can irritate skin, so handle pruning cuts with a little care.
See also
- Cyphostemma juttae — the flagship species
- Caudex · Soil and potting mix · Watering · Repotting
- Propagation — seed · Propagation — cuttings