Garden Q&A: My hydrangea is still flowering. When will I cut it?

Whether you're a gardening beginner or expert, Irish Examiner columnist Peter Dowdall has the answer to your questions 

There are still some flowers on my hydrangeas. I've never seen this occur before at this time of the year. I cut them back a few months ago and they have grown very big. When can I cut the shrub back again?

ANSWER

I suspect that in the time since this question was sent and now, the hydrangea blooms have been put to sleep by this week's drop in temperatures. 

It’s advisable to let the spent flower heads remain on the shrub through the winter as they act a bit like a blanket for the centre of the plant, trapping frost, ice and snow on the dead flower heads and extremities of the plant so protecting the new, dormant leaf buds lower down in the shrub.

Prune the shrub back in early March, just before the new growth starts but don’t cut it back too hard as you could end up with a shrub which won't flower for a year or two.

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