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Cushion Aloe

Haworthia retusa (hay-WORTH-ee-a re-TOO-suh)

Family: Asphodelaceae Non-native Groundcover (<1 ft)

The star cactus is small, perennial, succulent and is native of the Cape Provinces of South Africa. The plant is found in the semi-arid climate, growing in the shade of rocks or plants to protect itself from the sun. It is a member of the day lily family (Asphodelaceae). The specific epithet, retusa , is Latin for retusus that means "blunt" and refers to the plant's blunt leaf shape that curves backward like a thumb. This low maintenance plant prefers bright, indirect light. It can tolerate morning or late afternoon sun, but exposure to midday sun may cause leaf scorch. It requires well-drained succulent or cactus mix with added sand or perlite to encourage adequate drainage. The plant is drought tolerant, and overwatering may cause root rot. The potting medium should be allowed to dry out between waterings. Temperatures between 60 to 80 degrees Fahrenheit are ideal. It is hardy in USDA zones 10 to 11 and needs to be protected from frost. The humidity in most homes is well-tolerated by the star cactus. It is propagated by removing the offsets or pups that form at the base of the parent plant. The star cactus is small, slow-growing, and has a compact habit in the form of a star-shaped rosette. It measures up to 3 to 6 inches tall and 4 to 6 inches wide. The leaves are thick, fleshy, glossy, triangular, lime green, and have transparent tapered tips that curve backwards. Its flowers are small, tubular, and may be white or pale pink and appear on slender stems that measure up to 20 inches tall. The star cactus is a slow-growing, ornamental, and is suitable for use as a houseplant, desk plant, or terrarium. Insects, Diseases, and Other Plant Problems: Monitor for mealybugs, spider mites, aphids, and fungus gnats. Excessive watering can cause root rot. Fungal diseases like powdery mildew can result from wet leaves or overly humid conditions. The plant is sensitive to frost. Leaf burn can result from intense direct sunlight. This plant is non-toxic, but the sap may cause skin irritation. VIDEO Created by Laura Barth for "Houseplants, Succulents, and Cacti," a plant identification course created in partnership with Longwood Gardens. More information on Haworthia .

Source: NC State Extension Gardener Plant Toolbox ↗ NC State Extension Gardener Plant Toolbox, 48 attributes.

How it fits the guild

Guild layer 5 - Groundcover (<1 ft) Optimal soil pH Alkaline (>8.0); Neutral (6.0-8.0)
See companions & conflicts ↓

Companions & Conflicts

Curated pairwise relationships between this plant and others in the library — who feeds whom, who competes, who confuses the pests. Green reads as a good pairing, red as one to avoid.

No curated interactions recorded for this species yet.

Also noted by NC State

Related species the NC State Plant Toolbox flags for this plant — look-alikes to tell apart, and plants that play a similar role in a planting. Ones we carry in the library are linked.

Full plant profile

Growing Conditions
Plant type
Herbaceous Perennial; Houseplant; Succulent
Life cycle
Perennial
USDA zones
10a, 10b, 11a, 11b
Light
Partial Shade (Direct sunlight only part of the day, 2-6 hours)
Soil texture
Loam (Silt); Sand; Shallow Rocky
Soil pH
Alkaline (>8.0); Neutral (6.0-8.0)
Soil drainage
Good Drainage | Occasionally Dry
Available space
Less than 12 inches
Mature size
Height: 0 ft. 3 in. - 0 ft. 6 in. | Width: 0 ft. 4 in. - 0 ft. 6 in.
Growth rate
Medium
Maintenance
Low
Canopy layer
5 - Groundcover (<1 ft)
Form & Appearance
Habit / form
Dense; Erect
Leaf color
Green
Leaf type
Simple
Leaf arrangement
Rosulate
Leaf shape
Deltoid
Leaf margin
Entire
Leaf feel
Fleshy; Smooth
Leaf value
Showy
Leaf size
1-3 inches long
Hairs present
No
Leaf detail
The thick, lime green, triangular leaves are somewhat truncated, the tops covered by a translucent "window" that gives the leaf its triangular shape. The tips taper to a point. Bright light can cause many different colors to develop in the leaves.
Flower color
Insignificant; Pink; White
Flower form
Raceme
Flower shape
Tubular
Flower size
< 1 inch
Flower detail
Small, usually white or pale pink flowers in 20-inch tall racemes. Peduncle erect, simple, with a few sterile bracts; bracts membranous, small, lanceolate to ovate; pedicels short, ascending.
Bloom time
Spring; Summer
Fruit type
Capsule
Fruit detail
Capsule ovoid to oblong, 3-locular. Seeds with angles winged.
Wildlife & Ecology
Native status
Non-native
Origin
Southwest Cape Provinces of South Africa
Distribution
Cape Provinces
Play value
Colorful; Easy to Grow
Food & Medicine
Fruit type
Capsule
Landscape Use
Landscape location
Container; Houseplants; Patio
Design feature
Accent
Garden tags
#rock garden #window boxes #non-toxic for cats #non-toxic for horses #non-toxic for dogs #easy to grow #houseplant #container plant #easy to grow houseplant #pet friendly #succulent #drought tolerant #spreading #colorful leaves #attractive leaves #interesting leaves #herbaceous perennial
Problems & Resistance
Resistant to
Drought
Propagation
Division; Leaf Cutting

Planted at Hunnicutt

Nobody’s planted this one yet.