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What happened to my flowers on my big mophead Nikko Blue Hydrangea?
I have a few Nikko blue hydrangeas about 4 or 5 years and every year I'm big and beautiful blooms. But this year, I have a lot of blue flowers, but they are very small, looking almost like lacecap variety. Can anyone tell me what happened and what I can do to bring my big blooms next year. Also, one bushes died on one side. There are just sticks (I did break) and no new growth at all.
I bet you had a late frost which blocked the flowers already formed. Do not prune after July. The other half of the deaths were the seeds of new emerging next spring on the ground – no worries.
Hotel Nikko Blue