Ferocactus pilosus
| Light | Full sun; the more the better once established |
|---|---|
| Water | Moderate in the growing season, allowing the mix to dry between waterings; keep dry in winter |
| Soil | Gritty, fast-draining mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; roughly USDA zones 9–11 |
| Propagation | Seed (primary); occasionally by removing rooted offsets from a clump |
| Toxicity | Non-toxic to cats and dogs |
Ferocactus pilosus is a tall, columnar barrel cactus from northern Mexico, prized for its dense armour of vivid, blood-red spines interspersed with fine white bristly hairs. Young plants are solitary and roughly globe-shaped, but with age they elongate into stout columns and often cluster into impressive multi-headed groups, earning the common name Mexican fire barrel. It is a member of the genus Ferocactus, the true barrel cacti.
Description
Ferocactus pilosus begins life as a solitary green globe and gradually lengthens into a firm, ribbed column that can reach well over a metre tall in cultivation and considerably more in habitat, sometimes branching from the base to form dense clusters. The body is divided into numerous prominent ribs lined with closely set areoles.
Its most striking feature is the spination. Each areole bears a cluster of stiff central spines that emerge a brilliant red and mellow with age, accompanied by finer, hair-like white radial bristles that give the plant a softly whiskered look against the red. In summer the crown produces funnel-shaped flowers in warm shades of orange to red, followed by fleshy, scaly fruit.
Distribution and habitat
The species is native to the arid and semi-arid highlands of northern and north-eastern Mexico, across states including Coahuila, Nuevo León, Tamaulipas, San Luis Potosí and Zacatecas. It grows on rocky slopes, ridges and open scrub, often in gritty, well-drained ground and in full, unrelenting sun.
Like all cacti, the genus is listed under CITES Appendix II, so international trade in wild-collected plants is regulated. Nursery-grown seedlings are widely available and are the responsible choice for collectors.
Cultivation
Ferocactus pilosus is a robust, rewarding grower that repays generous light with the deepest red spine colour — plants grown too shaded produce paler, weaker spines and a softer, etiolated body. Plant it in a gritty, mostly mineral mix in a pot with ample drainage. Water thoroughly during the warm growing months once the mix has dried, then reduce sharply and keep the plant dry through a cool winter rest, which also improves the chances of flowering on mature specimens.
Large barrels appreciate room for their roots; see Repotting and Watering for general technique. Protect from hard frost, though established plants tolerate brief cold if bone dry.
Propagation
Seed is the usual and most reliable method. Sown on a warm, mineral surface and kept humid, the seeds germinate readily, and seed-grown plants develop the strongest spination. Clustering specimens occasionally offer rooted offsets that can be detached and grown on; see Propagation — seed and Propagation — offsets for details.
Common problems
- Rot — the commonest cause of loss, usually from a slow-draining mix or watering during cold, dormant spells; the plant softens and discolours from the base.
- Weak spine colour — insufficient light produces pale, sparse spines rather than the signature fiery red.
- Etiolation — too little sun makes the body narrow and stretch upward, losing its stout barrel form.
- Pests — mealybugs (white fluff among the areoles) and red spider mites (fine webbing, bronzed skin) are the typical offenders; see Pests and diseases.
See also
- Ferocactus — the genus overview
- Soil and potting mix · Watering · Repotting
- Propagation — seed · Propagation — offsets