Neolloydia conoidea
| Light | Bright light with some direct sun; a sunny windowsill or greenhouse spot |
|---|---|
| Water | Sparingly; allow the mix to dry fully between waterings, and keep dry through winter |
| Soil | Very free-draining mineral mix, ideally with added limestone grit (see Soil and potting mix) |
| Temperature | Keep above freezing; roughly USDA zones 9–11 |
| Propagation | Seed (primary); occasional offsets from the few plants that branch |
| Toxicity | Non-toxic to cats and dogs |
Neolloydia conoidea is a small cactus from western Texas and northern Mexico, prized by collectors for its neat conical tubercles, its crisp black-and-white spination and its vivid magenta flowers. Usually solitary, over many years a plant may branch from the base into a low, few-headed clump, each stem topped by silky blooms that seem oversized for so modest a plant. It is the best-known member of the genus Neolloydia and often reaches hobbyists under its older names.
Description
Neolloydia conoidea produces short cylindrical stems, typically a few centimetres thick and up to around 20 cm tall (occasionally to about 24 cm). Plants are often solitary but may branch from the base to form small clusters over many years. The stem surface is broken into distinct conical tubercles arranged in gently spiralling rows, each tubercle tipped with an areole bearing a spreading crown of spines.
The spination is the plant's signature: numerous pale, whitish radial spines (often around fifteen or more) frame one to a few darker central spines, often near-black, so that each areole reads as a small starburst of contrasting light and dark. From the woolly stem tips, funnel-shaped flowers open in a bright magenta to violet-pink, broad and glossy, and unusually large in proportion to the slender stems that carry them.
Distribution and habitat
The species is native to western Texas in the United States — along the Rio Grande in the Big Bend region — and to several states of northern and central Mexico, ranging as far south as Querétaro, where it grows in arid scrub, rocky slopes and grassland. It favours calcareous (limestone) ground, tucking in among rocks and low vegetation that afford a little shelter. In habitat it endures strong sun, sharp drainage and long dry spells, contracting and resting through drought.
Cultivation
Neolloydia conoidea is a fairly obliging plant for a collector, provided its roots are never left wet. Grow it in a very free-draining, mostly mineral mix; a little added limestone grit suits its natural preference for alkaline ground. Give it bright light with plenty of direct sun to keep the body compact and the spination strong, and to encourage the magenta flowers.
Water thoroughly once the mix has dried out completely during the growing season, then allow it to dry again before the next drink. Keep the plant dry and cool over winter, which both prevents rot and helps set flower buds for spring. As with most desert cacti, overwatering and a slow-draining medium are the chief dangers; see Watering and Repotting for general technique.
Propagation
Seed is the primary method and germinates readily on a warm, gritty surface kept lightly humid; see Propagation — seed for a full walkthrough. Because some plants branch and offset, you can also detach rooted offsets from the base when they are available and pot them up once any cut surface has callused — see Propagation — offsets. Grafting is not usually necessary, as the species grows well enough on its own roots.
Common problems
- Rot — nearly always from overwatering or a mix that holds moisture; stems soften and discolour from the base.
- Etiolation — too little light causes weak, elongated growth and washed-out spines, spoiling the compact form.
- Pests — mealybugs (white fluff in the tubercle axils and roots) and red spider mites (fine webbing, bronzed skin) are the usual offenders. See Pests and diseases.
See also
- Neolloydia — the genus overview
- Soil and potting mix · Watering · Repotting · Propagation — seed · Propagation — offsets