Starfish Cactus, including species like Stapelia, Huernia, and Orbea, are succulents known for their striking, star-shaped flowers and fleshy, angular stems. Though they resemble cacti, they belong to the milkweed family. Native to South Africa, their unique appearance and relatively low maintenance make them a popular choice.
Starfish Cactus Essential Care
Starfish Cactus thrives in bright, indirect light. While they tolerate some morning sun, intense afternoon rays can scorch stems, turning them reddish or purple. Insufficient light causes etiolation, making stems leggy and stretched. An ideal location is near a south-facing window indoors or in filtered light outdoors.
Watering is crucial for these succulents, which store water in their thick stems. Use a “soak and dry” method, allowing soil to dry completely between waterings to prevent root rot. Overwatering is common, especially during cooler, dormant months when less moisture is needed. During active growth in spring and summer, more frequent watering may be necessary, but always ensure proper drainage.
Well-drilling soil is essential to prevent waterlogging. Use a specialized cactus or succulent potting mix, amended with perlite, pumice, or coarse sand, for aeration and drainage. Pots must have drainage holes. These plants prefer being somewhat root-bound, so repotting is only needed every two to three years to refresh the soil.
Starfish Cactus prefers warm temperatures, ideally 70-95°F (21-35°C) during active growth. They are not frost-tolerant and need protection below 50°F (10°C), which can damage the plant and hinder flowering. While they handle typical household humidity, drier air is preferred; excessive humidity, especially with cold, can cause fungal issues.
Fertilizing is not always necessary, as Starfish Cactus adapts to nutrient-poor soils. If desired, apply a balanced liquid succulent fertilizer sparingly at half-strength during spring and summer. Over-fertilizing can cause excessive foliage growth, fewer blooms, and root burn. Cease fertilization during cooler, dormant months.
Encouraging Starfish Cactus Blooms
The distinctive, star-shaped flowers are a primary attraction. Adequate light, at least six hours of bright, indirect sunlight daily, encourages robust growth and flowering. A period of cooler winter temperatures, above 50°F but below active growth, can also trigger blooming by mimicking natural dormancy.
Consistent “soak and dry” watering during the growing season also contributes to bloom production. Allowing the plant to become slightly root-bound can encourage flowering, as this mild stress prompts energy focus on reproduction. Flowers range from reddish-brown to purple, often with intricate patterns and a hairy texture.
Many Starfish Cactus species emit a strong, often unpleasant odor resembling rotting meat. This scent attracts flies and other insects, serving as primary pollinators. While the smell can be intense, individual flowers typically last only a few days. The plant may produce multiple blooms over several weeks from late summer to fall.
Troubleshooting Common Issues
Overwatering frequently causes soft, mushy stems and root rot. If symptoms appear, stop watering immediately and let the soil dry completely. Using a pot with good drainage and a gritty soil mix prevents this issue.
Conversely, shriveling or wrinkled stems indicate underwatering or root uptake problems. Though drought-tolerant, these plants need consistent moisture during active growth. Increase watering slightly in hot, dry conditions, but always maintain the “soak and dry” cycle.
Starfish Cactus can be susceptible to common houseplant pests like mealybugs and spider mites. Regularly inspect stems and undersides to detect infestations early. Treat promptly with insecticidal soap or horticultural oil.
Propagating Starfish Cactus
Propagating Starfish Cactus is straightforward, primarily through stem cuttings. The best time is during warmer months (spring or summer) when the plant is actively growing. Select a healthy, non-flowering stem section, 3 to 5 inches long, and make a clean cut.
After cutting, allow the end to “callus” or dry out for several days to two weeks. This forms a protective layer, preventing rot when planted. Once callused, plant it shallowly in a well-drilling succulent or cactus mix.
Place the potted cutting in bright, indirect light. Water very lightly only after a week or more, allowing the soil to dry between applications, to encourage root development without causing rot. Roots typically form within a few weeks to a month, after which the new plant can be cared for like a mature specimen.