Pelecyphora aselliformis
| Light | Bright light with some protection from the harshest afternoon sun |
|---|---|
| Water | Sparingly; let the soil dry fully between waterings, dry rest in winter |
| Soil | Very free-draining, mostly mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; roughly USDA zones 9b–11 |
| Propagation | Seed (primary); occasionally offsets on clustering plants |
| Toxicity | Not known to be toxic to cats or dogs; not a food plant |
Pelecyphora aselliformis is a small, slow-growing cactus from the state of San Luis Potosí in central Mexico, prized by collectors for its curious, sculptural surface. Its most distinctive feature is a covering of flattened, comb-like (pectinate) spines set on laterally compressed, hatchet-shaped tubercles, which give rise to the common names hatchet cactus and peyotillo (little peyote). Despite that folk name and a long-standing reputation as a "peyote imitator," it is a distinct species and the resemblance is superficial. In spring and summer it is topped by bright magenta to violet-pink flowers.
Description
Pelecyphora aselliformis forms a solitary or slowly clustering, globose to shortly cylindrical body, usually only a few centimetres across and reaching perhaps 10 cm tall on old plants. The stem is firm and grey-green to blue-green, and — unlike most cacti — its tubercles are strongly flattened from side to side, so that each one is narrow and blade-like rather than conical. This is the trait behind the "hatchet" name.
Along the crest of every tubercle sits an elongated areole bearing many small, chalky spines fused into two neat opposing rows, like the teeth of a comb. This pectinate arrangement lies flat against the body and is soft to the touch rather than sharp. Flowers appear from the woolly crown in spring and summer, opening magenta to purplish-pink and only a few centimetres across; they last a few days each in bright conditions.
Distribution and habitat
The species is native to the semi-arid highlands of San Luis Potosí in central Mexico, where it grows on limestone-derived soils among low scrub and grasses. In habitat the plants often sit low among rock and litter, partly shaded by surrounding vegetation, and endure a long dry season followed by summer rains.
Wild populations are limited and have long been under pressure from over-collection. Like the rest of the genus, Pelecyphora is strictly protected under CITES (the genus is listed on the most restrictive appendix), so wild-collected plants may not be traded across borders. Nursery-raised, seed-grown plants, by contrast, are legal to own and are the only responsible source.
Cultivation
Pelecyphora aselliformis is a rewarding but slow subject that dislikes excess moisture at the root. Grow it in a snug pot in a gritty, mostly mineral mix with excellent drainage, and give it bright light with a little shade from the fiercest afternoon sun to keep the body compact and well-coloured. Because its natural soils are limestone-based, many growers add a little extra grit or crushed limestone, though this is not essential.
Water thoroughly only when the soil has dried right out, then let it dry again; taper off in autumn and keep the plant dry and cool through winter, which helps prevent rot and encourages flowering. Some collectors graft this naturally slow species to speed up young plants, though it grows perfectly well on its own roots with patience. See Watering, Repotting and Grafting for general technique.
Propagation
Seed is the standard and most reliable method. The fine seed is sown on a warm, mineral surface kept humid until germination, after which seedlings are grown on carefully as they are slow in their early years — see Propagation — seed for a full walkthrough. Plants that cluster with age can occasionally be divided or have offsets removed and rooted; see Propagation — offsets.
Common problems
- Rot — the most frequent cause of loss, almost always from overwatering or a slow-draining mix; the body softens and discolours from the base or crown.
- Etiolation — too little light makes the plant grow pale and unnaturally tall, losing its neat, low form.
- Pests — mealybugs (white fluff tucked among the tubercles) and red spider mites (fine webbing and a bronzed, dull surface) are the usual offenders. See Pests and diseases.
See also
- Pelecyphora — the genus overview
- Grafting · Soil and potting mix · Watering · Propagation — seed · Propagation — offsets