How to prune garden phlox 'david'

Mid-to-late summer for deadheading; autumn for cutting back; spring for stem thinning. Deadhead by cutting the spent panicle back to the next lateral shoot. In spring, remove the weakest stems at ground level leaving 5–7 strong shoots per clump. Cut all growth to soil level in autumn after first frost.

Deadhead continuously in summer; thin in spring; cut back each autumn. Garden Phlox 'David' benefits from deadheading to extend bloom and prevent self-seeding of inferior offspring. Cut spent flower heads back to a side-shoot or lateral bud. In autumn, cut the entire plant to the ground once foliage dies back. Thinning stems to 5–7 per clump in spring improves airflow and reduces powdery mildew.

Deadhead by cutting the spent panicle back to the next lateral shoot. In spring, remove the weakest stems at ground level leaving 5–7 strong shoots per clump. Cut all growth to soil level in autumn after first frost.