Ariocarpus retusus var. furfuraceus, often referred to as the "star cactus," is a fascinating and highly prized variety within the Ariocarpus genus. This variety is native to the arid regions of Northern and Central Mexico and is particularly noted for its unique and striking appearance, as well as its adaptability to cultivation under the right conditions. Here's a detailed description and some cultivation tips for this beautiful plant.
Description
Ariocarpus retusus var. furfuraceus is characterized by its slow-growing, geometrically shaped, succulent body, which is mostly underground with only the crown visible above the soil. The crown is flat or slightly rounded, with triangular tubercles that are more pronounced and elongated compared to the typical Ariocarpus retusus. The surface of the tubercles is covered in a whitish or greyish wool, which gives the plant its specific name "furfuraceus," meaning bran-like or scaly. This protective layer helps the plant conserve moisture and reflects sunlight, reducing water loss.
The plant blooms in late fall, producing large, funnel-shaped flowers that are usually pink or white. The flowers emerge from the woolly areas at the top of the plant, adding a striking contrast to its otherwise subdued appearance.
Cultivation Tips
Light: Ariocarpus retusus var. furfuraceus requires plenty of sunlight to thrive but should be protected from the harsh midday sun, especially during the hottest months. A spot that receives bright, indirect light or morning sun is ideal.
Soil: Well-draining soil is crucial to prevent root rot. A cactus or succulent potting mix, ideally amended with extra perlite or pumice for enhanced drainage, works well.
Water: Water sparingly, allowing the soil to completely dry out between waterings. Over the summer months, when the plant is actively growing, you can water more frequently, but always ensure the soil is dry before watering again. In winter, reduce watering significantly, as the plant enters a period of dormancy.
Temperature: Ariocarpus retusus var. furfuraceus prefers warm temperatures but can withstand cooler temperatures during its dormant period in the winter. However, it should be protected from frost, which can damage the plant.
Feeding: Feed with a diluted, low-nitrogen cactus fertilizer during the growing season to support its slow growth. Do not feed during dormancy.
Repotting: Due to its slow growth, repotting is rarely needed. However, if you do need to repot (typically every few years to refresh the soil), do so in the warmer months when the plant is more resilient.
Pests/Diseases: Watch out for root rot due to overwatering and pests like mealybugs, which can hide in the crevices of the tubercles. Treat pests with an appropriate insecticide and always ensure proper watering practices to prevent rot.
