Pruning. It always comes back to pruning.
So here it is my fellow gardeners the skinny on pruning hydrangeas and lilacs.
Hydrangeas don’t need to be pruned unless they have become overgrown and unsightly. Try to keep any cuts made above the first set of large leaves or only cut down to the last healthy buds.
Bigleaf types (mophead & lacecap) when pruning do in late summer after flowering has ceased. Do not cut any stems that haven’t bloomed as they will flower the following season. Deadhead spent blooms and cut back stems to the last bud.
Annabelle type prune in summer after spring blooming.
Lilacs need to be pruned right after flowering to keep them from growing too tall and unmanageable. Cut back one third of branches and trim out inner branches to increase air and light. Also cut away shoots growing near ground sprouting from the main trunk. Do not prune any later as buds set in the branches for the next spring’s blooms.