UK pruning guide · RHS timing
When to prune agrimony in the UK
Why the timing differs here
For shrubs that flower on the current season's growth, the RHS times pruning to early or mid spring — after severe weather has passed and once the growth buds begin to swell. In Britain that is usually March into April rather than the February common in warmer regions; prune too early and the new shoots meet a late frost.
How to prune agrimony
Cut all stems to just above ground level with secateurs in autumn or early spring. Deadhead the tall spike inflorescences in summer if self-seeding is unwanted.
Agrimony is a low-maintenance herbaceous perennial that dies back naturally each winter. Cut the whole plant down to ground level in autumn or early spring once stems are spent. During the growing season, removing the tall flower spikes before seed set reduces unwanted spread.
More agrimony care for British gardens
Care at a glance
Pruning agrimony in the UK — FAQ
When should I prune agrimony in the UK?
Prune agrimony in early to mid spring. For shrubs that flower on the current season's growth, the RHS times pruning to early or mid spring — after severe weather has passed and once the growth buds begin to swell. In Britain that is usually March into April rather than the February common in warmer regions; prune too early and the new shoots meet a late frost.
Is it illegal to prune agrimony in spring or summer in the UK?
Pruning itself is not illegal, but destroying an active nest is. Under the Wildlife and Countryside Act 1981 it is a criminal offence to damage or destroy the nest of any wild bird while it is being built or in use, and the RHS treats the nesting season as March to August, sometimes longer. Check agrimony for nests before cutting, and if you find an active one, leave that part of the plant until the birds have fledged.
How do you prune agrimony?
Cut all stems to just above ground level with secateurs in autumn or early spring. Deadhead the tall spike inflorescences in summer if self-seeding is unwanted.
How often does agrimony need pruning in a British garden?
Once annually; deadhead as needed in summer. Agrimony is a low-maintenance herbaceous perennial that dies back naturally each winter. Cut the whole plant down to ground level in autumn or early spring once stems are spent. During the growing season, removing the tall flower spikes before seed set reduces unwanted spread.
Why is UK pruning timing different from American advice?
Most pruning guides online are written for US conditions and anchored to USDA zones. Britain's maritime climate gives milder winters but later, less predictable last frosts — from March in the south-west to mid-May in the north — so the RHS advises against winter pruning for most plants: it pushes out soft growth that a late frost then kills. Britain also has the nesting-bird law, which has no US equivalent.