You are cutting the blooms off. Do not prune them in the fall or winter.
If they are too big for the space, move them and pick something smaller.
Pat


mark wrote:

I have a couple of hydrangia's that seem to grow well. They just don't
get many flowers, if any., I think it is because I prune them back every
winter. I don't want them to get huge and grow out of the space I have
them in. Is there a proper time and way to prune them?
thanks,
mark