Gymnocalycium stellatum ssp. occultum

Gymnocalycium stellatum ssp. occultum (Till & Till): A small, slow-growing cactus from Argentina with a particularly bumpy stem. It tends to be gray-green to brown in color and has 7-11 low, rounded ribs. Each woolly areole sports 3-5 spines that curve back slightly toward the stem. At maturity, it can reach about 4.0" in diameter and produces several large, white flowers atop its stem.

This cactus variety will not survive a hard frost, but if there is a risk of freezing temperatures it can be brought indoors to grow on a sunny window sill or under a grow light. Cactus need bright sunlight, great drainage, and infrequent water to prevent rot. Pick containers with drainage holes and use well-draining cactus and succulent soil with 70% to 80% mineral grit such as coarse sand, pumice, or perlite. Water deeply and wait for the soil to completely dry out before watering again. Keep dry in winter.

Full Cactus Guide