How to Grow and Care for Haworthia Cooperi

Haworthia cooperi, also known as Cooper’s Haworthia or Window Haworthia, is a small succulent native to South Africa prized for its appearance. The plant forms tight rosettes of fleshy leaves that feature translucent tips. These “windows” are an adaptation allowing sunlight to penetrate the inner leaf tissue for photosynthesis. This slow-growing succulent grows only a few inches tall and wide, making it well-suited for indoor collections.

Haworthia Cooperi Care Guide

Light

This plant thrives in bright, indirect sunlight. An ideal location is near an east-facing window that receives gentle morning sun or set back from a south-facing window. Too much direct sunlight will scorch the leaves, causing them to develop a reddish or white appearance as a stress response.

Insufficient light causes etiolation, where the plant stretches and its rosettes become less compact. The leaves may also appear pale as the plant reaches for a light source. If you notice this stretching, moving it to a brighter location is necessary. Supplemental grow lights can also provide the intensity needed to keep the plant healthy.

Water

Haworthia cooperi should be watered using the “soak and dry” method to prevent root rot. This involves watering the plant thoroughly until water drains from the pot’s bottom holes, then allowing the soil to dry out completely before the next watering. You can check the soil’s moisture by inserting a finger about an inch deep; if it feels dry, it is time to water.

During the spring and summer growing season, watering may be needed every two to three weeks. In the fall and winter, the plant’s growth slows, and it enters a semi-dormant period. During this time, watering frequency should be reduced to as little as once a month to prevent oversaturation and root decay.

Soil

Haworthia cooperi requires a loose, fast-draining potting medium to prevent water from lingering around its roots. A commercial cactus or succulent mix is a good choice for this plant, as these mixes are formulated to provide the necessary aeration and drainage.

To create your own mix, combine regular potting soil with an equal amount of an inorganic material like perlite, pumice, or coarse sand. This amended soil will have a grittier texture that allows water to pass through freely, providing a healthy foundation for its root system.

Temperature and Humidity

Haworthia cooperi prefers average household temperatures between 65°F and 80°F (18°C to 27°C). It is not frost-tolerant and must be protected from temperatures that dip near freezing. If grown outdoors, it is hardy in USDA zones 9 through 11 but should be brought inside if a frost is expected.

This succulent prefers low humidity, which is another reason it fares well as a houseplant. High humidity can contribute to fungal issues, especially without enough air circulation. Avoid misting, as water collected in the dense rosette can lead to rot.

Fertilizer

These plants are adapted to nutrient-poor soils, so fertilizing is not a strict requirement. However, a small amount of nutrients during the active growing season can encourage health. A balanced succulent or cactus fertilizer, diluted to half-strength, can be applied once in the spring and again in the summer.

Avoid fertilizing during the fall and winter when the plant is dormant. Always water the plant before applying fertilizer to prevent it from burning the roots.

Propagating Haworthia Cooperi

Propagating Haworthia cooperi is easily done by dividing the offsets, or “pups,” that grow from the base of the mother plant. This method is reliable and creates new plants that are genetically identical to the parent. Wait until an offset is about a third of the size of the main plant to ensure it has enough resources to survive on its own.

To begin, gently unpot the plant and carefully separate the pup from the main root ball. You may be able to tease it apart with your fingers, or you might need a clean, sharp knife. Allow the separated offset to sit in a dry, shaded place for a few days so the cut area can form a callus, which prevents rot when planted.

Once the wound has callused, plant the pup in a small container filled with a fast-draining succulent soil mix. Keep the soil lightly moist for the first couple of weeks to encourage new root growth. Place the new plant in a location with bright, indirect light and care for it as you would a mature plant.

Repotting Haworthia Cooperi

As a slow-grower that prefers being slightly root-bound, this plant does not need frequent repotting. Repot every two to three years, or when offsets have filled the pot. The best time to repot is in the spring or early summer during the plant’s active growing period. Repotting provides more space and freshens the soil.

When it is time to repot, choose a new container that is only one or two inches wider in diameter than the old one. A pot that is too large can hold excess moisture, increasing the risk of root rot. Ensure the new pot has a drainage hole at the bottom.

To repot the plant, remove it from its current container and gently shake off the old soil from the roots. Place the plant in the new pot, fill it with fresh, well-draining succulent mix, and water it thoroughly.

Common Problems and Solutions

Common issues with Haworthia cooperi are almost always related to its environment and care routine.

• Overwatering: Signs include mushy, yellowing, or overly translucent leaves, indicating potential root rot. To resolve this, allow the soil to dry out completely and adjust your watering schedule to be less frequent.
• Insufficient Light: Stretching, pale color, and widely spaced leaves are signs of etiolation. Move the plant to a location with more bright, indirect sunlight to encourage compact growth.
• Underwatering: Shriveled, thin, or puckered leaves indicate the plant is thirsty. A deep watering should help the leaves become plump again within a day or two.
• Pests: Mealybugs can occasionally appear as small, white, cottony masses at the base of the leaves. Treat them by dabbing the pests with a cotton swab dipped in isopropyl alcohol.