Portulacaria afra
| Light | Bright light to full sun; tolerates part shade indoors |
|---|---|
| Water | Regular in warm growth; let soil dry between waterings, sparse in winter |
| Soil | Free-draining gritty mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 9b–11 |
| Propagation | Cuttings (very easy); also branches and offsets |
| Toxicity | Non-toxic to cats and dogs; leaves are edible and grazed by wildlife |
Portulacaria afra is a fast-growing, soft-wooded succulent shrub from southern Africa, easily recognised by its glossy reddish-brown stems and dense sprays of small, rounded green leaves. Tough, forgiving and quick to branch, it is a mainstay of warm-climate landscaping and one of the most popular subjects for succulent bonsai, where it is fondly known by common names such as elephant bush, spekboom and dwarf jade. Despite the "dwarf jade" nickname it is not closely related to the true jade plant (Crassula ovata); it belongs to the genus Portulacaria in the family Didiereaceae.
Description
Portulacaria afra is a much-branched, semi-woody shrub that in the ground can reach 2–4 m tall, though in pots and bonsai it is kept far smaller. The stems are the plant's signature: smooth, succulent when young and colouring to a warm reddish-brown or purplish tone, they arch and cascade with age. Along them sit pairs of small, obovate to nearly circular leaves, thick and glossy, usually 1–2 cm long, that stay a fresh mid-green in good light.
The plant stores water in both leaves and stems, letting it shrug off drought. Under strong sun and lean conditions the growth tightens and the stems redden further, while shade produces looser, greener, more sprawling growth. Small, star-shaped pink flowers can appear in clusters toward the stem tips, but flowering is irregular in cultivation and the plant is grown mainly for its foliage and form.
Distribution and habitat
The species is native to the dry thicket, or "spekboomveld", of the Eastern Cape and adjoining arid regions of South Africa, extending into neighbouring parts of southern Africa. It grows on rocky slopes and in semi-arid scrub, often as a dominant thicket plant, and is an important browse plant for elephants, kudu, tortoises and other wildlife — hence the "elephant bush" and "elephant food" names.
Spekboom is also valued ecologically for its ability to establish easily from broken branches and for its efficient, drought-adapted photosynthesis, which has made it a favourite in South African landscape restoration and greening projects.
Cultivation
Few succulents are as forgiving. Portulacaria afra thrives in bright light to full sun, which keeps the leaves compact and the stems well coloured; indoors it wants the brightest window available or it will stretch. Grow it in a free-draining, gritty mix and water regularly through the warm growing season, letting the soil dry between drinks. In winter, or whenever growth slows, water sparingly — the plant tolerates dryness far better than sogginess.
It is frost-tender, so bring it in or protect it where temperatures drop below freezing. Feed lightly during active growth, and prune freely to shape it: the species responds to cutting with dense, twiggy regrowth, which is exactly why it makes such rewarding bonsai. Repot when it fills its container; see Repotting and Watering for general technique. A prostrate, cascading form (prostrata) and a cream-and-green variegated form are widely grown, the latter needing a touch more sun to hold its colour and being a little slower and more tender.
Propagation
Propagation could hardly be simpler. Stem cuttings of almost any size root readily: take a piece, let the cut end callus for a day or two, then set it in a gritty mix and keep it lightly moist until roots form. Even branches knocked off and left on the soil surface will often strike on their own. Because the plant roots so easily, it is almost always grown from cuttings rather than seed, which keeps named forms true. See Propagation — cuttings for a full walkthrough.
Cultivars
Several forms are common in the trade:
- variegata — leaves marbled cream and green, sometimes pink-tinged in strong light; slower and more sun-hungry than the plain green form.
- prostrata — a low, trailing habit that spills over pot edges and walls, popular in hanging containers.
- Dwarf / small-leaf forms — tighter, smaller-leaved selections favoured for miniature bonsai.
Common problems
- Rot — the main killer, caused by overwatering or a slow-draining mix; stems soften and blacken, especially in cold, wet winters.
- Leaf drop — sudden shedding of leaves usually signals drought stress, a hard move, or cold; the plant typically recovers once conditions steady.
- Etiolation — too little light produces long, weak, sparse stems with widely spaced leaves and washed-out colour.
- Pests — mealybugs (white fluff in leaf axils) and the occasional spider mite are the usual visitors; see Pests and diseases.
See also
- Portulacaria — the genus overview
- Crassula ovata — the true jade plant, often confused with dwarf jade
- Bonsai · Soil and potting mix · Watering · Propagation — cuttings · Repotting