How to Prune deep purple African daisy?
No pruning required, but deadheading will prolong flowering

deep purple African daisy · Osteospermum ecklonis
Grow in light, moderately fertile, very well-drained soil in a warm site in full sun with shelter from cold winds; in frost-prone climates, propagate reserve plants every year, and overwinter young plants in frost-free conditions
No pruning required, but deadheading will prolong flowering