How to Prune moss phlox?
No pruning required

moss phlox · Phlox subulata
Also known as: ground pink; rock phlox; flowering moss; moss pink; mountain pink
Will perform best in well-drained fertile soil in a sunny or dappled shade positon, prefering full sun and avoiding waterlogging. Can be trimmed back in autumn to rejuvenate and shape.
No pruning required