Now is the time to prune your woody, sun-loving panicle type Hydrangeas (like Limelight, Quickfire, Diamond Rouge Little Lamb, Pinky Winky, Fire Light, Little Lime, Strawberry Sundae, Vanilla Strawberry and any other species in this group).
The best rule of thumb is to cut back these woody plants by reducing about 1/3 of the length of last year’s growth, removing the brown flower heads that remain on the plant.
Leave the overall shape somewhat rounded and the stems somewhat irregular for a more natural form as the new growth emerges.