How to Fertilize Scheer's hedgehog cactus?
Very dilute low nitrogen cactus feed in warm growth season

Scheer's hedgehog cactus · Echinocereus scheeri
Grow in cactus compost in full light. From midspring to early autum water moderately and apply a half-strength balanced liquid fertiliser monthly; keep completely dry at other times. See houseplant cacti and succulent cultivation for further information
Very dilute low nitrogen cactus feed in warm growth season