Answer: There's generally nothing you need to do for hydrangea for the winter. You could wait until after the first hard frost and then prune the branches back a little so they don't whip around in the wind, and then put a layer of mulch over the ground beneath the plant to help insulate the roots. Major pruning is done in the spring just as buds begin to swell on the branches. At that time you can prune away any winter damage and shorten the length of the stems if the plant is getting too large.
Best wishes with your hydrangea!
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