Q: I have six different big leaf hydrangeas all in a row. Only one is blooming. Any idea what’s going on? 2 of them are the Endless Summer variety. Should they all be pruned prior to August?
A: When healthy big leaf hydrangeas don’t bloom, it’s almost always due to flower bud damage. Their flower buds form in fall, so maybe they were pruned after August the previous year. Maybe there was cold weather at the wrong time which froze the buds in winter.
In my experience, all of the big leaf hydrangeas should be pruned, if needed, after the first big flush of blooms in June. I use the week of July 4 as my target date to prune my big leaf hydrangeas. Reblooming hydrangeas, like Endless Summer, will bloom lightly a couple more times after July.
Your shrubs look healthy and I don’t see a need to prune them, but again, if you need to prune get it done the first week in July.