Why doesn't my Hydrangea bloom?

It is very healthy - lots of big green leaves - just one bloom.

Why doesn't my Hydrangea bloom?
You said that you trimmed a lot. Did you cut the old stems?, meaning previous year's growth. If you want the flowers next season, you only want to trim the dead flowers, which means, if you prune hard, you have to give up enjoying the flowers next year. The hydrangea produces flowers on previous year's growth, so if you prune it way back, it won't bloom next season. Let it grow again, and you should see more flowers next spring/summer. Don't worry!
Reply:I think you may have inadvertently trimmed off all of the buds for this year. Hydrangeas are funny about being pruned and it should be kept to a minimum. I would recommend only cutting off dead wood and thinning out the shrub every couple of years by removing only a few older branches. If you leave it alone it should spring back just fine next year.
Reply:did you trim the hydrangea back alot this year? if so it could've gone into shock. or believe it or not sometimes plants can go into hybernation. rhodedendrian plants tend to do this. so next year your hydrangea should be a ok!

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