Prune in late winter or early spring after the worst frost has passed
Remove dead, damaged, or diseased stems first
Cut out weak, thin, or crossing branches
Remove spent flower heads if needed
For old wood bloomers, only trim lightly and avoid cutting healthy buds
For new wood bloomers, cut stems back to about one-third of their height
Use clean, sharp pruning shears
Make cuts just above a healthy bud or leaf node
Remove about one-third of the oldest stems at the base for renewal
Avoid heavy pruning in fall
Disinfect tools after pruning
Water the plant after pruning if the soil is dry