Haworthiopsis coarctata
| Light | Bright light to a little direct sun; leaves colour up in strong light |
|---|---|
| Water | Moderately in the growing season; let the soil dry between waterings, keep drier in winter |
| Soil | Free-draining gritty mix (see Soil and potting mix) |
| Temperature | Keep above freezing; USDA zones 10a–11b |
| Propagation | Offsets, stem cuttings and seed |
| Toxicity | Non-toxic to cats and dogs |
Haworthiopsis coarctata is a columnar South African succulent whose short, incurved leaves stack tightly around a slowly elongating stem, forming a dense, upright column. Grown in bright light the leaves flush a warm red-brown, a colour change that makes it a favourite among collectors of the genus Haworthiopsis. It was long known as Haworthia coarctata, and much older literature still uses that name.
Description
Haworthiopsis coarctata grows as an upright to sprawling column, with fleshy, triangular leaves pressed closely against the stem and each other so that the growing point sits atop a tidy spiral of overlapping leaves. Individual leaves are dark green, thick and incurved at the tips, their outer surfaces scattered with small, pale tubercles that give the plant a lightly banded, pebbled texture. In strong light and under cooler, drier conditions the whole column takes on a bronzed red-brown to purplish tone, fading back to green in shade.
As stems lengthen they tend to lean and eventually recline, and the plant readily offsets from the base and along the stem to build up clumping colonies over time. The small, tubular greenish-white flowers are carried on a slender, wiry inflorescence and are modest compared with the architectural appeal of the foliage.
This species is closely related to, and often confused with, Haworthiopsis reinwardtii; the two share the stacked-column habit, but H. coarctata generally has broader, more closely appressed leaves and a stouter column.
Distribution and habitat
The species is native to the Eastern Cape of South Africa, where it grows on rocky slopes and among scrub, often tucked into the shelter of other vegetation or rock. In habitat it experiences bright light, sharp drainage and seasonal dry spells, and the reddish stress colouring seen in cultivation reflects the exposed conditions many wild plants endure.
Cultivation
Haworthiopsis coarctata is an easy, forgiving succulent and a good choice for beginners. Grow it in a free-draining, gritty mix in bright light; a little direct sun brings out the best red-brown colouring, though very intense afternoon sun through glass can scorch the leaves. Water moderately while the plant is in active growth, letting the mix dry out between waterings, and cut back in winter to keep it on the dry side and prevent rot.
Being a stacking, clumping grower, it appreciates a pot with room to offset and benefits from occasional repotting once a clump fills its container or a leaning column needs resetting. See Watering for general technique.
Propagation
This is one of the simplest haworthias to increase. Offsets that form at the base or along the stem can be detached and rooted (see Propagation — offsets), and lengths of stem taken as cuttings will root readily once the cut surface has callused. Seed is also possible but slower and less commonly used by hobbyists. See Propagation — seed for the seed-raising approach.
Common problems
- Rot — the main risk, caused by overwatering or a poorly draining mix; stems soften and blacken from the base.
- Etiolation — too little light stretches the column and spaces the leaves apart, losing the tight stacked look and the red colouring.
- Pests — mealybugs (white fluff between the leaves and at the roots) are the most frequent nuisance; see Pests and diseases.
See also
- Haworthiopsis — the genus overview
- Haworthiopsis reinwardtii — a similar stacking species
- Soil and potting mix · Watering · Propagation — offsets · Propagation — cuttings · Repotting