The Roadkill Cactus, scientifically known as Stapelia gigantea, is a distinctive succulent that captivates with its unusual appearance. Also known as the Zulu Giant or Carrion Flower, this fascinating plant stands out in any collection. Its unique characteristics evoke curiosity, making it a popular choice for those seeking something out of the ordinary. It is a unique and captivating addition to any plant collection.
Understanding Roadkill Cactus
Stapelia gigantea is native to arid regions of Southern Africa, including South Africa and Tanzania. This plant features fleshy, four-angled stems that can reach up to 10 inches tall. Its most striking feature is large, star-shaped flowers, which can grow up to 16 inches in diameter, making them among the largest in the plant kingdom. These pale yellow or cream-colored flowers are often adorned with thin red stripes and covered in fine hairs.
The common name “Roadkill Cactus” comes from the flower’s unusual scent, likened to rotting meat. This pungent odor attracts flies and other insects for pollination. Despite the aroma, especially noticeable on hot afternoons, its striking appearance makes it a low-maintenance succulent for indoor cultivation. While a succulent, Stapelia gigantea is not a true cactus; it belongs to the milkweed family (Apocynaceae).
Caring for Roadkill Cactus
Light Needs
The Roadkill Cactus thrives in bright, indirect light. Indoors, a south-facing window is ideal for ample brightness without harsh, direct exposure. It tolerates some morning or late afternoon sun, but intense midday sun can cause sunburn or reddish discoloration on stems. Stretched or leaning stems indicate a need for more light.
Watering
Proper watering is important for Stapelia gigantea health, as overwatering is a common issue. Use the “soak and dry” method: water thoroughly until drainage, then allow the soil to dry completely before rewatering. During spring and summer, water every two to three weeks, reducing frequency significantly in winter. The plant is drought-tolerant, storing water in its fleshy stems; shriveling stems indicate a need for water.
Soil Requirements
Good drainage is important for the Roadkill Cactus to prevent root rot. A specialized cactus or succulent potting mix is recommended for quick drainage. Amending standard potting mix with 50% to 70% perlite, pumice, or coarse sand further enhances drainage. A shallow pot with drainage holes also helps manage moisture.
Temperature and Humidity
Stapelia gigantea prefers warm temperatures, ideally 65°F to 95°F (18°C to 35°C) during its active growing period. It is sensitive to cold and should be protected from temperatures below 50°F (10°C), as prolonged exposure causes damage. While it tolerates typical indoor humidity, it appreciates slightly higher humidity during the growing season. If grown outdoors, bring it indoors before temperatures consistently drop.
Fertilizing
Fertilizing is not always necessary but can encourage vigorous growth and blooming during the active season. If fertilizing, apply a balanced liquid fertilizer diluted to half strength once a month in spring and summer. Avoid fertilizing during fall and winter dormancy. Over-fertilization can harm the plant.
Propagating Roadkill Cactus
Propagating Stapelia gigantea is most commonly done through stem cuttings. To propagate, select a healthy, mature stem and use a clean, sharp knife or shears. Allow the cut end to dry and form a callus for several days to weeks in a cool, shady location with good airflow. This callusing prevents rot once planted.
Once callused, plant it in a small pot with well-draining cactus or succulent potting mix. Insert the callused end into the soil and water sparingly until roots develop. Rooting typically occurs within a few weeks to months.
While seed propagation is possible, it is more time-consuming and complex for home growers. Seeds require consistent warmth and humidity to germinate, making cuttings the preferred method.
Common Roadkill Cactus Issues
Root rot, primarily caused by overwatering, is the most common problem. Symptoms include soft, mushy, or rotting stems. If rot is detected, unpot the plant, remove affected parts, and repot healthy sections in fresh, dry, well-draining soil. Conversely, underwatering causes shriveling or wrinkled stems.
Insufficient light can lead to a lack of blooms; ensure the plant receives adequate bright, indirect light. Pests like mealybugs and spider mites can affect Stapelia gigantea. Mealybugs appear as small, cottony masses and can be wiped away with rubbing alcohol. Maintaining good airflow helps prevent fungal issues and pest infestations.