I have two Endless Summer hydrangeas in my yard - I have had them for several years. They have always bloomed sporadically - some years they have lots of blooms and some years very few.
Last year I had ZERO blooms. The previous year I had a handful of blooms between the two.
After zero blooms last summer - the Endless Non-Blooming Summer - I gave up on them and decided thatin the spring I would dig them up and move them some where else in the yard where they would be less visible.
This spring I had very little time for gardening so I didn't move them and guess what happened? They bloomed more than they ever have - each shrub has at least 50 blooms! I don't know why - I did not fertilize them. Actually, I completely ignored them. Normally I have to trim off the dead wood since in my Massachusetts garden they die back almost to the ground every year, but this year they did not die back. I'm assuming because we had a lot of snow this year so they were well insulated?
Has anyone else had this happen with their Endless Summers? Maybe it was all the rain we got this year? It's a mystery to me.
Here are some pics: