Vanilla Strawberry Hydrangea blooms on new growth. I would wait until you see leaf buds and leaves growing in the early spring. Trim off any broken branches and branches that aren’t showing any signs of life. If you want to cut back the top to encourage heavier branching, do it early before the flower buds form. If you wait too long, you run the risk of cutting off the buds and then going a year without flowers.
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