Rebutia minuscula
| Light | Bright light with some direct sun; a little shade from the harshest afternoon sun |
|---|---|
| Water | Regularly in the growing season, letting the mix dry out between waterings; keep dry and cool in winter |
| Soil | Fast-draining mineral mix (see Soil and potting mix) |
| Temperature | Keep above freezing; a cold, dry winter rest suits it well (roughly USDA zones 9–11) |
| Propagation | Seed and offsets; also easily grafted |
| Toxicity | Non-toxic to cats and dogs |
Rebutia minuscula is a small, low-growing cactus from the mountains of northwestern Argentina and the type species of the genus Rebutia. Its flattened, deep-green globes stay only a few centimetres across but ring themselves with a generous crown of red-orange funnel-shaped flowers that emerge from around the base each spring, a habit that has earned the genus the common name crown cactus. Undemanding, quick to flower and readily offsetting, it is one of the most beginner-friendly cacti in cultivation.
Description
Rebutia minuscula forms a small, flattened to shortly globular body, typically only a few centimetres in diameter, that clusters freely with age to build up low cushions of heads. The stem is a fresh mid- to deep green, arranged into low spiralling ribs broken up into small tubercles. From each areole radiate short, fine, pale to whitish bristly spines that lie close to the body and give little in the way of fierce armament.
The flowers are the plant's great attraction. Unlike many cacti that bloom from the crown, Rebutia produces its flowers low down, from areoles near the base of the stem, so the blooms appear to encircle the plant. They are funnel-shaped, glossy red to orange-red, and open widely in sunshine over a period of several weeks in spring. Even young, small plants flower willingly, and a well-grown clump can almost hide itself under bloom.
Distribution and habitat
The species is native to the highlands of northwestern Argentina, in the region of Tucumán and neighbouring provinces, where it grows at moderate to high elevations. In habitat it roots among rocks and in gritty, well-drained ground on slopes, often tucked into crevices or growing among low vegetation and grass that offers a little shelter. The mountain setting means bright light, cool nights and a marked dry, cold season in winter — conditions worth keeping in mind in cultivation.
Cultivation
Rebutia minuscula is among the easiest cacti to grow and a fine choice for a first flowering plant. Give it a fast-draining, mostly mineral mix and a bright spot with some direct sun; a little protection from the fiercest afternoon glare keeps the body from scorching, but too much shade will reduce flowering and draw the plant up.
Water fairly freely through the warmer months, letting the mix dry between waterings, and then keep the plant dry and cool over winter. This cold, dry rest is the key to the spectacular spring display — plants kept warm and watered all year tend to flower poorly. It is a small plant, so a snug pot and an occasional repot into fresh gritty mix keeps it healthy. See Watering for general technique.
Propagation
The species is easily increased both by seed and by offsets. It clusters readily, and the small offset heads can be detached and rooted with little trouble — see Propagation — offsets. Seed germinates freely on a warm, mineral surface kept humid, and seedlings reach flowering size quickly; see Propagation — seed. Like most small globular cacti it also takes well to grafting, though its natural vigour on its own roots means grafting is rarely necessary.
Common problems
- Rot — the main risk, almost always from a slow-draining mix or from watering while cool and dormant; heads soften and discolour from the base.
- Poor flowering — usually a sign the plant was kept too warm and watered through winter, or grown in too little light; give it a proper cold, dry rest.
- Pests — mealybugs (white fluff in the areoles and among the offsets) and red spider mites are the usual culprits; see Pests and diseases.
See also
- Rebutia — the genus overview
- Grafting · Soil and potting mix · Watering · Propagation — seed · Propagation — offsets · Repotting