Haworthia (Zebra Cactus)

Haworthia, also commonly called zebra plant, pearl plant, star window plant, or cushion aloe, is a genus of small, slow-growing succulent plants native to Southern Africa. Haworthia attenuata, Haworthia fasciata, and Haworthia cooperi are among the most popular species favored by houseplant enthusiasts for their attractive rosettes and relatively easy care. These delightful succulents offer a range of textures and patterns, making them a captivating addition to any indoor garden.

At Gardencenterpoint.com, we are dedicated to providing comprehensive and user-friendly gardening resources. This article contains easy steps for Haworthia care, various Haworthia species you must have, and how to buy Haworthia plants. Continue exploring the best practical advice, and discover all that you’ll need to succeed in the rewarding world of succulents!

1. Haworthia Overview: Understanding These Unique Succulents

Haworthias are members of the Asphodelaceae family, specifically the subfamily Asphodeloideae. They share this family with other well-known succulents like Aloe and Gasteria. While they might resemble small Aloes, Haworthias are distinct in their generally smaller size, slower growth rate, and often, their unique translucent leaf windows. These “windows,” which are actually specialized leaf tissues, allow light to penetrate deeper into the leaf, aiding in photosynthesis, especially in their native, often shaded, habitats.

Common name	Zebra Plant, Pearl Plant, Star Window Plant, Cushion Aloe, and many others depending on species.
Botanical name	Haworthia spp. (species plural)
Family	Asphodelaceae
Subfamily	Asphodeloideae
Genus	Haworthia
Species	Varies greatly (over 60 recognized species) Examples
Origin	Southern Africa (primarily South Africa and Namibia)
Native	Southern Africa
Life cycle	Perennial
Plant type	Succulent
Hardiness zone	Generally 9-11 (USDA); most are not frost-hardy.
Sunlight	Bright, indirect light; some morning sun tolerated. Avoid intense afternoon sun.
Maintenance	Low
Water	Low; “soak and dry” method. Allow soil to dry completely between waterings.
Drainage	Well-Drained (essential)
Soil pH	6.0-8.0
Spacing	Typically 2-6 inches, depending on species and arrangement.
Flowering period	Spring and Summer (varies by species)
Height	Typically 1-8 inches (varies greatly by species)
Width	Typically 2-10 in. (varies)
Growth rate	Slow
Flower color	Typically white or pale pink (small, not very showy)
Stem color	Green (often obscured by leaves)
Leaf Color	Varies: green, brown, reddish, some with translucent areas.
Flower benefit	Not a primary feature; foliage is the main attraction.
Garden style	Rock Garden, Container Garden, Succulent Garden, Indoor Garden
Uses	Ornamental, Container, Dish Garden, Vertical Garden, Houseplant, Collections
Propagation	Offsets (pups), Leaf Cuttings (some species)
Fertilizer	Light feeding during growing season (spring/summer); diluted balanced fertilizer.
Toxicity	Generally considered non-toxic to humans and pets, but ingestion is not recommended.
Pests	Mealybugs, Scale Insects (relatively pest-resistant)
Diseases	Root Rot (primarily from overwatering)

The genus Haworthia is incredibly diverse, boasting over 60 recognized species and numerous cultivars. These plants typically form rosettes of fleshy leaves, which can be smooth, textured, striped, spotted, or adorned with translucent panels. Their colors range from vibrant greens to deep browns and even reds, depending on the species and growing conditions. Many Haworthias also produce small, white, or pale pink flowers on long, slender stalks, although the flowers are generally less showy than the foliage.

A study published in the journal Bradleya (the journal of the British Cactus and Succulent Society) in 2013, “A revised generic classification for the Alooidae (Asphodelaceae),” provides a comprehensive taxonomic overview of the Haworthia genus and its relatives. This research highlights the evolutionary relationships between Haworthias and other succulent genera, helping to clarify their classification.

The natural habitat of Haworthias is primarily the southern regions of Africa, particularly South Africa and Namibia. They thrive in rocky, well-drained soils, often under the shade of shrubs or rocks. This adaptation to low-light conditions makes them well-suited to indoor environments, where they can tolerate less direct sunlight than many other succulents. The adaptation allows Haworthia to perform the best way in low-light.

Haworthias’ ability to store water in their thick leaves makes them drought-tolerant, another feature that contributes to their ease of care. They prefer infrequent but thorough watering, allowing the soil to dry out completely between waterings. This mimics their natural environment, where they experience periods of rainfall followed by extended dry spells. Overwatering is a common pitfall for Haworthia owners, leading to root rot, a fungal disease that can quickly kill the plant.

Another key aspect of Haworthia care is providing the right soil. A well-draining potting mix is crucial to prevent waterlogging. Commercial cactus and succulent mixes are readily available, but you can also create your own by combining potting soil with perlite, coarse sand, or pumice.

2. Essential Haworthia Care: Watering, Light, Soil, and More

Successful Haworthia care hinges on understanding and replicating their natural environment. This involves careful attention to watering, light, soil, temperature, humidity, and fertilization.

Watering:

The “soak and dry” method is the golden rule for watering Haworthias. This means thoroughly watering the plant until water drains from the bottom of the pot, then allowing the soil to dry out completely before watering again. The frequency of watering will depend on several factors, including the size of the pot, the type of soil, the ambient temperature, and the humidity.

• Spring and Summer (Growing Season): Water more frequently, perhaps every 1-2 weeks, depending on conditions.
• Fall and Winter (Dormant Season): Reduce watering significantly, possibly to once a month or even less.

A good indicator of when to water is to check the soil moisture. Insert your finger about an inch into the soil; if it feels dry, it’s time to water. Alternatively, you can use a moisture meter.

Light:

Haworthias prefer bright, indirect light. They can tolerate some direct morning sun, but intense afternoon sun can scorch their leaves. A south- or east-facing window is often ideal. If you don’t have enough natural light, you can supplement with grow lights. LED grow lights are energy-efficient and provide the right spectrum of light for plant growth.

Signs of insufficient light include:

• Etiolation: The plant stretches towards the light source, becoming leggy and losing its compact rosette shape.
• Pale Color: The leaves lose their vibrant color and become pale green or yellowish.

Signs of too much light include:

• Sunburn: The leaves develop brown or reddish spots.
• Leaf Curling: The leaves may curl or shrivel.

Soil:

A well-draining potting mix is essential for Haworthias to prevent root rot. Here’s a breakdown of suitable soil components:

• Commercial Cactus and Succulent Mix: A convenient option readily available at most garden centers.
• DIY Mix: Combine equal parts of:
  • Potting soil
  • Coarse sand (horticultural sand, not play sand)
  • Perlite or pumice

Avoid using regular potting soil alone, as it tends to retain too much moisture. Adding inorganic materials like perlite and coarse sand improves drainage and aeration.

Temperature and Humidity:

Haworthias prefer average room temperatures between 65°F and 80°F (18°C – 27°C). They can tolerate slightly cooler temperatures in winter, but they should be protected from frost. Haworthias are not particularly sensitive to humidity levels and can thrive in typical household humidity.

Fertilizing:

Haworthias are not heavy feeders and only require light fertilization during the growing season (spring and summer). Use a balanced, water-soluble fertilizer diluted to half strength. Apply the fertilizer once a month or every other watering. Avoid fertilizing during the dormant season (fall and winter).

3. Haworthia Species Identification: A Guide to Popular Varieties

The Haworthia genus is incredibly diverse, with a wide range of species and cultivars. Here are some of the most popular and readily available varieties:

• Haworthia attenuata (Zebra Plant): This is one of the most common Haworthias, easily recognized by its dark green leaves adorned with white, raised tubercles (bumps) that form horizontal bands, resembling zebra stripes. There are several varieties of H. attenuata, including:
  • Haworthia attenuata var. attenuata: The standard form.
  • Haworthia attenuata var. radula: Features narrower leaves and more numerous, smaller tubercles.
  • Haworthia attenuata ‘Concolor’: Lacks the white bands, having a uniform green color.
• Haworthia fasciata (Zebra Haworthia): Often confused with H. attenuata, H. fasciata is distinguished by having smooth, dark green leaves on the upper surface and white bands of tubercles only on the underside. The tubercles are typically smoother and less pronounced than those of H. attenuata.
• Haworthia cooperi: This species is known for its translucent leaves, which have a window-like appearance. The leaves are typically plump and rounded, forming a compact rosette. There are several varieties of H. cooperi, including:
  • Haworthia cooperi var. truncata: has flat topped leaves.
  • Haworthia cooperi var. pilifera: Features leaves with bristle-like hairs at the tips.
  • Haworthia cooperi var. venusta: Has particularly attractive, velvety leaves.
• Haworthia limifolia (Fairy Washboard): This distinctive species has triangular, ridged leaves that resemble a washboard. The leaves are typically dark green or brownish-green and have a rough texture.
• Haworthia retusa (Star Cactus): This species has thick, triangular leaves with translucent “windows” at the tips. The leaves are arranged in a star-like rosette.
• Haworthia truncata (Horse’s Teeth): One of the most unusual Haworthias, H. truncata has rectangular, truncated leaves that appear as if they have been cut off at the top. The leaves are arranged in two opposite rows, giving the plant a unique, flattened appearance.
• Haworthia cymbiformis (Cathedral Window Haworthia): has boat-shaped leaves.

This is just a small selection of the many Haworthia species available. Each species has its own unique characteristics and charm, making Haworthias a rewarding and collectible genus for succulent enthusiasts. Researching the specific needs of each species you acquire will ensure its long-term health and beauty.

4. Propagating Haworthia: Expanding Your Collection

Haworthias are relatively easy to propagate, allowing you to expand your collection or share these fascinating plants with friends. There are two primary methods of propagation: offset separation and leaf cuttings.

Offset Separation:

This is the easiest and most reliable method of propagating Haworthias. Offsets, also known as “pups,” are small, miniature plants that grow at the base of the mother plant.

1. Timing: The best time to separate offsets is during the spring or summer, when the plant is actively growing.
2. Removal: Gently remove the mother plant from its pot. Carefully separate the offsets from the mother plant, ensuring that each offset has some roots attached. You may need to use a clean, sharp knife or scissors to separate them if they are tightly connected.
3. Callousing: Allow the offsets to callous over for a few days to a week in a dry, shaded location. This helps to prevent rot when they are planted.
4. Planting: Plant the offsets in a well-draining cactus and succulent mix. Water sparingly until new growth is observed, indicating that the roots have established.

Leaf Cuttings:

While not as reliable as offset separation, propagating Haworthias from leaf cuttings is possible, although some species are more successful than others.

1. Selection: Choose a healthy, plump leaf from the mother plant. Gently twist and pull the leaf from the stem, ensuring that you get the entire leaf base.
2. Callousing: Allow the leaf cutting to callous over for several days to a week in a dry, shaded location.
3. Planting: Place the calloused leaf cutting on top of a well-draining cactus and succulent mix. You can also slightly bury the base of the leaf in the soil.
4. Watering: Mist the soil lightly every few days, keeping it slightly moist but not wet.
5. Patience: Rooting can take several weeks or even months. New growth will emerge from the base of the leaf, eventually forming a new rosette.

5. Troubleshooting Common Haworthia Problems

While Haworthias are generally low-maintenance plants, they can occasionally encounter problems. Here are some common issues and how to address them:

• Overwatering/Root Rot: This is the most common problem with Haworthias. Symptoms include:
  1. Yellowing, mushy leaves
  2. Wilting, despite moist soil
  3. A foul odor coming from the soil
• Solution:
  1. Remove the plant from its pot.
  2. Inspect the roots. Healthy roots should be firm and white or light-colored. If the roots are brown, mushy, and have a foul odor, they are rotted.
  3. Trim away any rotted roots with a clean, sharp knife or scissors.
  4. Allow the plant to callous over for a few days in a dry, shaded location.
  5. Repot the plant in a fresh, well-draining cactus and succulent mix.
  6. Water sparingly until new growth is observed.
• Underwatering: While less common than overwatering, underwatering can also cause problems. Symptoms include:
  1. Shriveled, wrinkled leaves
  2. Dry, crispy leaves
  3. Slow growth
• Solution: Water the plant thoroughly, allowing water to drain from the bottom of the pot.
• Sunburn: Too much direct sunlight can scorch Haworthia leaves. Symptoms include:
  1. Brown or reddish spots on the leaves
  2. Leaf curling or shriveling
• Solution: Move the plant to a location with brighter, less indirect light.
• Pests: Haworthias are generally pest-resistant, but they can occasionally be affected by mealybugs or scale insects.
  1. Mealybugs: These are small, white, cottony insects that feed on plant sap.
  2. Scale Insects: These are small, brown, immobile insects that attach themselves to the leaves and stems.
• Solution:
  1. Isolate the affected plant to prevent the pests from spreading.
  2. Remove the pests manually with a cotton swab dipped in rubbing alcohol.
  3. For severe infestations, you can use an insecticidal soap or neem oil.
• Etiolation (Stretching): This occurs when the plant is not receiving enough light. The plant stretches towards the light source, becoming leggy and losing its compact rosette shape.
  Solution: Move the plant to a brighter location or supplement with grow lights.

6. Where to Buy Haworthia and What to Look For

Haworthias are becoming increasingly popular and are now readily available at many garden centers, nurseries, and online retailers. Here’s what to look for when purchasing a Haworthia:

• Healthy Appearance: Choose a plant with firm, plump leaves that are free from blemishes, spots, or signs of pests or disease.
• Compact Rosette: Look for a plant with a tight, compact rosette shape. Avoid plants that are leggy or stretched, which indicates insufficient light.
• Well-Drained Soil: Check the soil to make sure it is well-draining. Avoid plants that are sitting in soggy soil.
• Root System: If possible, gently remove the plant from its pot to inspect the roots. Healthy roots should be firm and white or light-colored. Avoid plants with brown, mushy roots.
• Species Identification: If you are looking for a specific species, make sure the plant is correctly labeled.

7. Haworthia Display and Design Ideas

Haworthias’ small size and attractive forms make them ideal for a variety of display options:

• Individual Pots: Showcase individual Haworthias in small, decorative pots that complement their unique shapes and colors. Terracotta pots are a classic choice, as they provide good drainage and breathability.
• Mixed Succulent Arrangements: Combine Haworthias with other succulents of similar light and water requirements to create visually appealing arrangements. Consider using different textures, colors, and heights to add interest.
• Dish Gardens: Create miniature landscapes in shallow dishes using Haworthias, other succulents, rocks, and decorative gravel.
• Vertical Gardens: Haworthias can be incorporated into vertical gardens or living walls, adding a touch of greenery to small spaces.
• Terrariums: While Haworthias can be grown in terrariums, it’s crucial to choose open terrariums that provide good air circulation. Closed terrariums can create excessive humidity, leading to rot.

When designing with Haworthias, consider the following:

• Light: Place your Haworthias in a location that receives bright, indirect light.
• Watering: Remember to water thoroughly but infrequently, allowing the soil to dry out completely between waterings.
• Soil: Use a well-draining cactus and succulent mix.
• Aesthetics: Choose containers and companion plants that complement the unique beauty of your Haworthias.