Answer: Hydrangeas are pruned in the early spring, just as the buds begin to swell on the stems. The easiest way to maintain these shrubs is to cut all the stems down to about 18-24" and then remove some of the oldest (thick, gray) stems all the way down to the crown of the plant. New flowering stems will emerge from those stems which you have shortened. This type of renewal pruning will keep your hydrangeas a manageable size and will ensure flowering each year.
Best wishes with your garden!
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