Answer: Big Leaf Hydrangeas (Hydrangea macrophylla) bloom on new shoots which develop on old wood. To keep your hydrangea under control you'll want to prune it back in the early spring, just as the leaf buds begin to swell on the branches. You can cut everything down to about knee-high. This will provide enough old wood for new shoots to develop and produce new blooms. Don't cut it back now; wait until spring. Best wishes with your hydrangea!
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