Just found a great site I think you could use. Go to www.helpfulgardner.com, there was all kinds of stuff about hydrangeas, and why they might not bloom. One of the reasons was the winter frost being to tough on them, and late pruning.
If you prune them late in the season, it isn't helping them. Hope this helps you out. Good luck.
If you prune them late in the season, it isn't helping them. Hope this helps you out. Good luck.