Discocactus horstii (2007)

By Chris Deem (October 2007)

It’s a hot night, but no one would call it humid. The sky is clear and the stars are out, but no one would call it bright.

You smell them long before you see them. Large and deathly white, scented flowers loom above the small, deflated globes. The bodies are hard but fragile. Most are brown and a few are green. Even though they are half-buried in rocks and sand, their ribs are very prominent. The white areoles and tiny spines on the ribs add to the look of emaciation.

Between the fragile bodies and short-lived blossoms, small cephaliums stand. White, hard and still growing, they try to hide their brown bristles and spines.

Here and there are other signs of life, some moss and lichens, but they seem to fade away. The darkness envelops all, leaving only the cacti on this hot night, on the side of a mountain, in Minas Gerais, Brazil.

If you are lucky enough to see a healthy Discocactus horstii, you will know its caretaker is an experienced grower. These extremely sensitive cacti are often grown as grafted plants and are rarely grown on their own roots in cultivation.

The silica sand and rocks in which D. horstii grow are difficult to replicate in a pot. Be sure to use a slightly acidic, very porous mix. In their natural habitat, the rains come more often than you might expect. Water them fairly often and carefully with distilled or slightly acidic water. These cacti also require bright light and warmth all year long.