RHS Pruning Groups
The RHS Pruning Groups help to group woody plants by broad pruning principles.

Timing - Usually late winter/early spring, but sometimes late summer
Difficulty - Easy to moderate
The pruning methods explained below are for individual types and species of hydrangea.
The most commonly grown hydrangeas in gardens are lacecaps and mopheads – mopheads are identified by their full, roundish heads of large petals; lacecaps have tiny flowers in the centre of the bloom and an outer border of large petals.
Most pruning is carried out in late winter or early spring. However, climbing hydrangeas are pruned after flowering in summer.