Spiraea (Spiraea × cinerea): when and how to prune

Spiraea (Spiraea × cinerea): when to prune it?

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Straight after flowering, in May. It flowers on last year’s wood.

What else to prune in those months? May

Spiraea (Spiraea × cinerea): how to prune it?

1. Shorten the flowered branches by a third or back to a strong side shoot.
2. Every 2–3 years, remove a quarter of the oldest branches at the base to keep the shrub young.
3. Remove dead, damaged and crossing branches completely.
4. An old, bare shrub can be cut back to 20–30 cm above the ground after flowering; it will regrow.

How much to cut, and how often?

• One pruning period a year: May.
• Prune in moderation: never remove more than about a third of the shrub at once.

What does it mean for wildlife?

• Pruning in May can fall in the nesting season (15 March–15 August). Check carefully for nesting birds first: disturbing an active nest is against the law.
• Spiraea (Spiraea × cinerea) flowers in April–May, when it attracts bees.
• If pruning falls during flowering, wait until it is over or leave part of the plant to flower, so bees and butterflies still benefit.
• Prunings can go on a dead hedge or brash pile in a corner of the garden: shelter for hedgehogs, wrens and insects.

Common mistakes

• Clipping without first checking for nesting birds.
• Leaving a stub or sawing flush with the trunk: cut just outside the branch collar.

Nearby: related pruning guides

• Spiraea
• Foam of May (Spiraea × arguta)
• Japanese spiraea
• Thunberg spiraea (Spiraea thunbergii)
• Birchleaf spiraea (Spiraea betulifolia)
• Bridal wreath (Spiraea × vanhouttei)

Plant profile: Spiraea (Spiraea × cinerea) · Pruning calendar and basic rules