Timing Prune according to the hydrangea species and when it sets buds (on old or new wood). Most pruning is done in late winter or early spring, except for climbing hydrangeas which are pruned after flowering in summer.
Deadheading Remove faded flower heads to prevent seed development and encourage more blooms. Cut back the stem to the first strong, healthy pair of buds below the dead flower.
Pruning Established Plants Cut out 1-2 of the oldest stems at the base to encourage new growth. Overgrown plants can be renovated by cutting all stems at the base, but this will remove flowers for that year.
Pruning Climbing Hydrangeas Cut back any overly long shoots immediately after flowering. Extensive pruning should be staggered over 3-4 years to avoid reducing flowers.
Pruning Other Hydrangea Species H. serrata and H. paniculata flower more with annual pruning to a framework of branches.
Cut back last year's stems to a pair of healthy buds each spring. Hard prune to the lowest pair of buds for larger flowers on upright stems.
Pruning Damaged Wood If frost damages stems in spring, prune back to the first undamaged buds. Remove any weak, straggly, or ground-trailing stems.