How to Prune Ferocactus emoryi subsp. rectispinus?
No pruning required

Ferocactus emoryi subsp. rectispinus · Ferocactus emoryi subsp. rectispinus
Grow under glass in a loam-based potting compost with added extra grit. Water moderately when in growth, not at all when dormant. Apply a balanced liquid fertiliser 2 or 3 times in the growing season. See houseplant cacti and succulent cultivation for further advice
No pruning required