How to Plant & Care for Ferocactus

Place potted ferocactus plants in the warmest and sunniest available location during the spring and summer. Many ferocactus plants are cold hardy and can survive freezing temperatures. You can leave them outdoors during the winter in mild areas with minimum average temperatures around 45 degrees Fahrenheit; alternately, you can bring potted ferocactus indoors during the winter and keep it on a cool, bright windowsill.

Water the ferocactus regularly during the warm summer months. Allow the surface of the soil to dry out between irrigation. Reduce watering during the colder months, when your ferocactus will be dormant, to a light watering every few weeks. Do not keep potted ferocactus on dishes, as waterlogging will cause rot, especially during the wet winter months.

Repot ferocactus only when its roots completely fill their pot or they have become top-heavy. Choose heavy clay pots for stability. Add compost formulated for cactus or a peat-based compost containing 50 percent sharp sand or gravel. Wear gloves when handling ferocactus, as the stiff spines can puncture the skin. Do not water repotted ferocactus for the first few days.

Plant the ferocactus plants outdoors in mild areas with little or no frost. Choose a sunny location with well-drained soil and no danger of waterlogging. The exact cold tolerance of ferocactus varies depending on the species. Ferocactus hamatacanthus is among the hardiest species; it will grow well in areas within U.S. Department of Agriculture Plant Hardiness Map zone 6 that have average low temperatures of at least zero degrees Fahrenheit.