Pachypodium lamerei
| Light | Bright light to full sun; the more the better once acclimatised |
|---|---|
| Water | Regularly in warm growth; keep nearly dry through winter dormancy |
| Soil | Fast-draining mineral-rich mix (see Soil and potting mix) |
| Temperature | Warmth-loving; keep above 10 °C, ideally USDA zones 10–11 |
| Propagation | Seed (primary); occasionally by removing basal offsets or cutting the top |
| Toxicity | The stiff spines are the main hazard; toxicity to people and pets is poorly documented |
Pachypodium lamerei, widely known as the Madagascar palm, is a spiny, succulent-stemmed member of the dogbane family Apocynaceae native to southern Madagascar. Despite its common name it is not a palm at all: it forms a stout, silvery cylindrical trunk armed with dense spines, topped by a rosette of long, glossy strap-shaped leaves that gives it a superficially palm-like silhouette. It is by far the most widely grown species in the genus Pachypodium and a common sight as an indoor container plant.
Description
Pachypodium lamerei develops a thick, water-storing trunk that is grey to silvery-brown and clothed in clusters of hard, needle-sharp spines arranged around raised tubercles. In cultivation it is usually seen as an upright, sparingly branched column, though old specimens — especially in habitat — can become large and candelabra-like, sometimes reaching several metres tall.
The leaves are long, narrow and leathery, deep green with a pale midrib, and are carried in a spiralling crown at the growing tips. They are shed as conditions turn cool or dry, so the plant is often partly or fully deciduous over winter. Mature plants can produce showy, fragrant white flowers with yellow throats, borne near the crown in the warmer months; flowering is far more reliable on large plants grown outdoors in suitable climates than on smaller indoor specimens.
Distribution and habitat
The species is endemic to the arid and semi-arid south and southwest of Madagascar, where it grows in dry, sunny scrub and among rocks in seasonally hot conditions with a pronounced dry season. Like many thick-stemmed succulents from this region, it survives long droughts by storing water in its swollen trunk and by dropping its leaves. As with the whole cactus and succulent trade, wild collection is discouraged; the plants seen in cultivation are overwhelmingly nursery-raised from seed.
Cultivation
Pachypodium lamerei is one of the more forgiving members of its genus and adapts well to life as a houseplant, which is a large part of its popularity. Give it the brightest position you can — a sunny south-facing window indoors, or full sun outdoors once hardened off — as too little light causes weak, stretched growth. Grow it in a very free-draining, mostly mineral mix and a pot only a little larger than the rootball.
During the warm growing season water thoroughly whenever the soil has dried, and feed occasionally with a dilute balanced fertiliser. As temperatures fall and the plant sheds its leaves, cut watering right back and keep it nearly dry and warm through winter; cold, wet roots are the fastest route to rot. Protect it from frost at all times. See Watering and Repotting for general technique.
The spines are hard and sharp, so handle the plant with care and site it away from where people brush past it.
Propagation
Seed is the standard and most reliable method. Fresh seed sown on a warm, gritty, lightly moist surface germinates readily, producing the swollen little seedling trunk that makes young plants so appealing. Because the species branches only reluctantly, cuttings are less commonly taken, but a removed offset or a cut top can sometimes be rooted after allowing the wound to callus in warm, dry air. See Propagation — seed and Propagation — cuttings for full walkthroughs.
Common problems
- Rot — by far the most common killer, caused by overwatering, a slow-draining mix or cold wet conditions; the trunk softens and discolours, often from the base.
- Leaf drop — normal and expected as the plant enters winter dormancy or after a move; only a concern if paired with a soft trunk.
- Etiolation — insufficient light produces thin, pale, weak growth and sparse spination.
- Pests — mealybugs (white fluff in the crown and leaf axils) and spider mites (fine webbing, stippled leaves) are the usual offenders. See Pests and diseases.
See also
- Pachypodium — the genus overview
- Soil and potting mix · Watering · Repotting · Propagation — seed · Propagation — cuttings · Pests and diseases