Q.Mophead Hydrangea Didn’t Bloom
My MIL cut back our hydrangeas last year and they did not bloom this year. Should I prune them or leave them alone? One of the three did not even grow.
Certified GKH Gardening Expert
They can be pruned, but It is important to do so right after blooming. Your hydrangea type blooms on old wood, also. This will mean that you should leave older growth, or there will be no flowers, since it will not flower on first years growth. (New growth)
Here are some articles that will help:
https://www.gardeningknowhow.com/ornamental/shrubs/hydrangea/mophead-hydrangea-care.htm
Mophead hydrangeas are best planted where they can attain their estimated size at maturity and then do not prune them except to remove crossing branches or to remove leafless stems that do not leaf out (they can leaf out as late as the first half of June in NC). Big Leaf Hydrangeas like yours should now be loaded with dormant spring 2024 flower buds inside the stem ends so pruning now or starting somewhere between July-September) is not advisable. Last season, there was an Arctic Blast on December 22nd that affected hydrangea blooms as far south as Texas and Georgia, reducing or eliminating blooms by some mopheads in 2023. Many plants lost all stems and the roots then developed new stem growth in spring to replace the dead wood, essentially giving the plants the equivalent of a hard prune so all growth started from the crown/base of stems and there was little growth or even an actual shrinkage in plant dimensions. Fertilize with a slow release after all danger of frost has passed (3rd-4th weeks of April in High Point, NC) through 3 months before your average date of first frost (the average is around the 1st-2nd weeks of November so stop around the 1st-2nd weeks of August).
