Japanese mahonia: when and how to prune

Japanese mahonia: when to prune it?

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After flowering, in April. It needs little pruning.

What else to prune in those months? April

Japanese mahonia: how to prune it?

1. Cut overlong, bare stems back to just above a rosette of leaves or a few buds lower down; they will reshoot there.
2. Renovate an old, leggy shrub over two to three years: each year cut a third of the oldest stems back low.
3. Remove dead and damaged stems at the base.
4. Leave the faded sprays in place if you want berries for the birds.

How much to cut, and how often?

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

What does it mean for wildlife?

• Pruning in April can fall in the nesting season (15 March–15 August). Check carefully for nesting birds first: disturbing an active nest is against the law.
• Japanese mahonia flowers in November–March, when it attracts bees.
• 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

• Barberry
• Japanese barberry
• Darwin’s barberry (Berberis darwinii)
• Oregon grape
• Paleleaf barberry (Berberis candidula)
• Warty barberry (Berberis verruculosa)

Plant profile: Japanese mahonia · Pruning calendar and basic rules