When is the best time to trim my hydrangea bush? While it looks very healthy now, there are only a few blossoms appearing. Perhaps, when I cut it back in the fall, affected this lack of blooms now. Please advise.
Pruning to control height or to remove old flower heads depends upon the type of hydrangea that you have and whether the hydrangea flowers on the previous or the current year’s growth.
If you are referring to the bigleaf (mophead) type of hydrangea, then pruning should be done after flowering. Most likely you cut off the flower buds, if you pruned in the fall. Some of the newer hydrangeas like the Endless Summer series bloom on old and new wood so you may see some bloom on the new wood this season. Take a look at pruning information for hydrangeas below.
Hydrangeas that flower on previous year’s growth:
Hydrangea macrophylla, Bigleaf hydrangea, Mophead (Pink & Blue types), Lacecaps
The bigleaf hydrangeas are the most common types in the landscape and flower on previous year’s growth. They can be susceptible to cold damage. Stems that have been damaged by cold should be pruned as soon as it is determined they are dead in the spring. Watch for new growth at the base of the plant. If the plant has basal shoots that are about 6 inches in length, but the upper parts are bare, then the bare stems need to be removed. Otherwise prune shortly after flowering is complete.
Some of the newer cultivars like “Endless Summer” bloom on both old and new wood, so if winter damaged, you may have summer blooms. To control height prune after the first flush of flowers.
Hydrangea quercifolia, Oakleaf hydrangea – Flowers on previous year’s growth. Typically does not require pruning but if needed, in spring only remove dead wood. Otherwise prune after flowering.
Hydrangeas that flower on the current year’s growth:
Hydrangea arborescens, Smooth hydrangea, “Annabelle”, Grandiflora
Prune anytime from late summer until early spring. If pruning in the early spring, try to prune before leaves appear.
Hydrangea paniculata, Panicle hydrangea, PeeGee hydrangea, “Limelight”
Prune anytime from late summer until early spring. If pruning in the early spring, try to prune before leaves appear. Thin or cut back to previous season’s growth. Can become overgrown if not pruned.