Answer: If they usually bloom for you but didn't this year, it is probably weather related. Hydrangeas bloom on new growth, but some need to develop new growth on old wood. If your hydrangeas froze down to ground level last winter there would be no old wood on which new flowering stems could develop. The new stems from this season will provide the old wood for next year's growth and your hydrangeas should bloom right on time next year. Hope this sheds some light on the problem.
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