Answer: I think you must have some variety of Hydrqngea macrophylla. I suspect winter hardiness is the problem. These are generally going to have trouble blooming in your area due to excess winter cold, even though they may be root hardy. They bloom on old wood that grew the year before, so any winter damage to the stems will reduce or eliminate blooming the following year. Spring frost damage and spring pruning would also limit or prevent blooming. You might try providing winter protection such as a wind break and possibly a wire mesh cylinder around the plant filled with oak leaves (these are non-packing, hold air and thus insulate) and topped with plastic to keep it dry; allow some gaps for air flow to avoid overheating or condensation. Remove it in the spring but be ready to shelter it from any frosts once the buds have begun to swell. Good luck!
Q&A Library Searching Tips