UK pruning guide · RHS timing
When to prune rex begonia 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 rex begonia
Pinch soft stem tips with your fingers or use sterilised scissors just above a node or leaf axil. For leggier stems, cut back to within 5–8 cm of the soil. Avoid wetting the cut surfaces; begonias are susceptible to stem rot.
Rex begonias benefit from occasional pruning to prevent legginess and encourage dense, colourful foliage. Pinch or cut back long bare stems to a node or leaf. Remove dead or damaged leaves regularly. After the plant goes semi-dormant in winter, trim it back by up to one-third to refresh vigour in spring.
More rex begonia care for British gardens
Care at a glance
- When to prune rex begonia in the UK — our other guide for the same plant
- General rex begonia pruning guide
- RHS hardiness ratings explained
Pruning rex begonia in the UK — FAQ
When should I prune rex begonia in the UK?
Prune rex begonia 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 rex begonia in spring or summer in the UK?
There is no nesting-bird restriction that realistically applies to rex begonia, since birds do not nest in it. The Wildlife and Countryside Act 1981 still protects any active nest you do find anywhere in the garden — the rule is about the nest, not the plant.
How do you prune rex begonia?
Pinch soft stem tips with your fingers or use sterilised scissors just above a node or leaf axil. For leggier stems, cut back to within 5–8 cm of the soil. Avoid wetting the cut surfaces; begonias are susceptible to stem rot.
How often does rex begonia need pruning in a British garden?
Light tip-pinching monthly during the growing season; harder cutback once a year in spring. Rex begonias benefit from occasional pruning to prevent legginess and encourage dense, colourful foliage. Pinch or cut back long bare stems to a node or leaf. Remove dead or damaged leaves regularly. After the plant goes semi-dormant in winter, trim it back by up to one-third to refresh vigour in spring.
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.