before the first frost
Hello Rita! Take a look at these links on how and when to do this!
Thank you so much! I’ll cut back in spring!
Hi Rita. I'm Cindy. I'm so glad you named the type of hydrangeas that you have. Because different types of hydrangeas should be cut back at different times in a year. Limelights benefit from heavy pruning every few years to control their size and improve their flowering capabilities. Limelight hydrangeas only bloom on new wood, so any heavy pruning or cutting back must be done in late winter or early spring before new growth emerges, since pruning at any other time of the year will disrupt their normally abundant flower display. Hoping this helps and wishing you well.