Haworthiopsis reinwardtii aka Zebra Wart

Haworthiopsis reinwardtii is one of the easiest succulents to grow and is excellent for beginners. It tolerates neglect well, thrives with minimal watering, and adapts to a range of light conditions from bright indirect to full sun. The plant has earned the Royal Horticultural Society's Award of Garden Merit, which considers ease of cultivation as a key criterion. The main risk is overwatering, which can cause root rot — when in doubt, water less.

Haworthiopsis reinwardtii is a slow-growing succulent that forms columnar rosettes typically reaching 5–15 cm tall, occasionally up to 20 cm, with individual rosettes spreading about 10 cm wide. The RHS estimates it takes 2–5 years to reach maturity. The plant freely produces offsets from its base, gradually forming dense, mat-like clusters that can spread wider than the individual rosettes. Its growth habit is described as mat-forming and clumping.

Haworthiopsis reinwardtii prefers temperatures between 10–26°C (50–80°F) and does not tolerate frost. Wikipedia and the RHS note it cannot endure prolonged exposure below 10°C, so in temperate regions it must be grown under glass or brought indoors during winter. In its native Eastern Cape habitat, winter temperatures range from 7–20°C and summer peaks reach around 26°C. Brief cold snaps to near 0°C can be tolerated but should be avoided.

The easiest method is by dividing offsets (pups) that form around the base of the mother plant. Wait until offsets have at least four leaves and some roots, then separate with a clean knife during spring or autumn repotting. Leaf cuttings are possible but less reliable for this species — allow cut leaves to callus before placing on soil. Seed propagation is the slowest method and requires cross-pollination between two genetically different plants.

Yes, Haworthiopsis reinwardtii produces small, tubular, pinkish-white flowers in spring. The flowers appear in lax racemes on slender stalks that can reach up to 30 cm long — significantly taller than the plant itself. The blooms are modest and not particularly showy; this plant is primarily grown for its architectural, tubercle-covered foliage rather than its flowers. In habitat, the flowers are pollinated by wasps and bees.

POWO (Kew Gardens) recognises five infraspecific taxa. Var. brevicula is a smaller, more compact form from near Grahamstown with rosettes only 4 cm in diameter. Form zebrina has prominent tubercles forming transverse white bands, creating a striking striped appearance. Form olivacea has smoother olive-green leaves with rounder tubercles. Form chalumnensis has more elongate, inward-bent leaves that can flush copper-red under drought or sun stress. Form kaffirdriftensis has longitudinal rows of clear white tubercles. Most are found near the Fish River in the Eastern Cape.

Haworthiopsis reinwardtii can grow outdoors year-round in USDA zones 9–11, where temperatures stay above freezing. It thrives in rock gardens, succulent beds, and containers in sunny to semi-shaded positions with excellent drainage. In cooler climates, it must be grown in containers that can be brought indoors before frost, or kept in an unheated greenhouse. SANBI recommends placing it in rocky gardens in sun or semi-shade, mimicking its natural cliff-face habitat.

Repot Haworthiopsis reinwardtii every 2–3 years in spring, or when the plant has outgrown its container or produced numerous offsets. Choose a pot only slightly larger than the root ball — these plants have shallow root systems and do well in small containers. Always use a pot with drainage holes; terracotta is ideal as it allows moisture to evaporate through the walls. Use a fast-draining cactus/succulent mix. Repotting time is also ideal for dividing offsets for propagation.

During the active growing season (spring and summer), water freely when the soil is dry and apply a dilute, low-nitrogen fertiliser fortnightly. In autumn and winter, the plant enters a semi-dormant rest period — reduce watering to keep the soil just barely moist and stop fertilising entirely. The RHS recommends standing the plant outside in summer for fresh air and better light, then returning it to a bright indoor position before temperatures drop below 10°C.

In its native Eastern Cape habitat, the small tubular flowers of Haworthiopsis reinwardtii are pollinated by wasps and bees. Locusts are also documented feeding on the flowers. For seed production in cultivation, cross-pollination between two genetically distinct plants is required — the species cannot self-pollinate effectively. Pollen can be transferred manually using a fine brush or coconut fibre strand between open flowers on different plants.

Yellow leaves on Haworthiopsis reinwardtii almost always indicate overwatering or root rot. If the leaves feel soft or mushy alongside the yellowing, check the roots immediately — healthy roots are white and firm, while rotting roots are brown and mushy. Remove the plant from its pot, trim any rotten roots, let the base callus for a few days, and repot in fresh, dry cactus mix. Going forward, allow the soil to dry completely between waterings.

Brown leaves can have several causes. Crispy, dry brown tips usually indicate underwatering or very low humidity. Brown, mushy leaves point to overwatering and root rot. Brown patches or bleached spots on one side suggest sunburn from sudden exposure to intense direct light — acclimate gradually to brighter conditions. Brown lower leaves that dry up naturally are normal as the plant grows upward and sheds old foliage. Inspect the specific pattern to identify the cause.

Drooping or wilting leaves on Haworthiopsis reinwardtii typically signal root rot from overwatering — the roots can no longer absorb water, causing the plant to lose turgidity despite wet soil. Less commonly, severely underwatered plants may also droop as leaves deflate from exhaustion of stored water. Check the soil: if wet and the base feels mushy, unpot the plant, remove rotten roots, and repot in dry mix. If the soil is bone dry, give it a thorough soak and the leaves should firm up within a day or two.

Mealybugs are the most common pest, appearing as white cottony masses in leaf crevices. Treat by dabbing with rubbing alcohol on a cotton swab or applying insecticidal soap. The RHS confirms susceptibility to mealybugs but notes the plant is otherwise generally disease-free. Root rot from overwatering is the biggest disease concern — prevent it with well-draining soil and careful watering. Fungal leaf spot can occur if water sits on leaves or humidity is too high; always water the soil directly and ensure good air circulation.

Haworthiopsis reinwardtii is naturally a slow grower, so don't expect rapid expansion. However, if growth seems unusually stagnant, the most common causes are insufficient light (the plant may also etiolate or stretch), exhausted soil nutrients (repot with fresh mix every 2–3 years), or root-bound conditions. Ensure it receives bright light, feed with a dilute low-nitrogen fertiliser during spring and summer, and check if the roots have filled the pot. Temperature extremes (too cold or too hot) can also pause growth.

Haworthiopsis reinwardtii is native to the Eastern Cape Province of South Africa, where it grows between the towns of Peddie, East London, and Port Alfred. It is found on dry rocky hills and cliff faces, both on exposed sides and in the shade of rocks, typically among herbs and tall shrubs. The region has a warm, temperate climate with winter temperatures of 7–20°C and summer peaks around 26°C. POWO classifies its native range as the Southern Cape Province within the subtropical biome.

Haworthiopsis reinwardtii requires no regular pruning. The RHS confirms that no pruning is needed. The only maintenance is removing dead or dried lower leaves as the plant grows upward, which can be gently pulled off or snipped with clean scissors. If the flower stalk has finished blooming, cut it off at the base to redirect energy back to the plant. Never cut healthy green leaves.

Dust can accumulate between the raised tubercles on the leaves. Gently brush away dust with a soft, dry paintbrush or use a can of compressed air for hard-to-reach crevices between tightly packed leaves. Avoid misting or wiping with a wet cloth, as moisture lingering on the leaves can promote fungal growth. If the plant gets particularly dirty, a brief rinse under lukewarm water is fine — just ensure the soil drains completely and the rosette dries quickly afterward.

Zebra Wart does best in dry soil and should only be watered sparingly.

The Zebra Wart is very susceptible to soil that is too wet, so it's essential to choose a potting soil that drains well and does not retain excessive moisture. A soil mix that includes plenty of perlite or vermiculite for drainage and some organic matter for nutrition is ideal. You can easily create this type of soil by adding a few handfuls of perlite to regular cactus soil from the store.

To ensure optimal growth, the Zebra Wart prefers bright indirect light for 6-8 hours each day. Insufficient light can result in slow growth and leaf drop, so it's important to find a well-lit location for this plant. Place it near a window, within a distance of 1 meter (3 feet), to enhance its potential for thriving.

Zebra Wart prefers dry environments, but by misting the plant or providing extra humidity, water will linger on the leaves and create an ideal environment for fungi that could be harmful.

The Zebra Wart is known for its slow growth and doesn't require fertilizing beyond its potting soil. Replacing the soil in its pot once a year should offer it sufficient nutrition. It's essential to remember that plants get their energy from the sun, not from fertilizers.

No verified data on the toxicity of this plant exists within Ploi's records. Should you, someone in your family, or your pet ingest plant material with an unknown toxicity level, it is recommended to seek medical advice.