Prune in late winter or early spring before new growth starts
Remove dead, damaged, or diseased stems
Cut back weak or crossing branches
Reduce the plant by about one-third to one-half
Make cuts just above a healthy pair of buds
Keep stronger stems to support larger blooms
Remove old flower heads if desired
Shape the plant to maintain a balanced form
Use clean, sharp pruning shears
Avoid pruning too late in spring or summer