Cutting back hydrangea bush in April
I did not cut back any of the limbs before winter and thought I should do it now before warmer weather. But when I cut back a few I see they are alive and green. Whereas all the other older (previously) cut back limbs are brown inside. The "live" limbs are 3 to 4 feet long.
Thank you for your question. As this Extension article indicates, the variety of hydrangea is important to knowing when and how to prune them: http://ccenassau.org/resources/-hydrangea-types-and-how-to-prune I hope this is helpful!