How to Prune Callistemon 'Red Clusters'?
Usually little pruning is needed. Lightly shape if necessary, removing dead, damaged or diseased shoots. Prune after flowering.

Callistemon 'Red Clusters' · Callistemon 'Red Clusters'
Grow in moist but well-drained, neutral to acid soil in full sun; established plants are drought resistant. In colder areas grow under glass in loam-based compost (JI No.2) in full light with good ventilation. Pot on or top dress in early spring
Usually little pruning is needed. Lightly shape if necessary, removing dead, damaged or diseased shoots. Prune after flowering.