Advice
RHS Help & Advice
Pruning summer-flowering shrubs
Shrubs flowering after mid-summer usually do so on the current season’s growth. All summer-flowering shrubs need the routine removal of damaged, diseased and dead wood. Individual pruning requirements vary, but they may be determined by reference to their differing characteristics of growth, outlined below, and by studying specimens of some of the examples mentioned.
Deciduous shrubs with flowers borne terminally on previous year's growth during mid-to late summer
Examples: Lace-cap and mop-head hydrangeas.
How to prune: In spring remove dead flower-heads back to the first, or pair, of strong buds, and cut out to near ground level one in four of the oldest stems (to encourage new ones from the base).
Deciduous shrubs producing new flowering stems annually from a low branch framework
Examples: Buddleja davidii, Caryopteris, Perovskia, Spiraea japonica.
Pruning: In early spring cut back all stems to within three to four buds of older wood.
Evergreen shrubs flowering on current or previous year’s wood; flowers often of secondary importance to foliage effect
Examples: Elaeagnus, Fatsia, hebes, Portuguese laurel, rosemary.
Pruning: No regular pruning, but in spring shorten or remove any too-vigorous or badly positioned growths. These shrubs can often be rejuvenated by hard pruning in spring.
Evergreen shrubs producing often numerous flowering shoots in late summer and autumn
Examples: Calluna, Erica vagans, lavender, Santolina.
Pruning: In spring cut back flowered shoots to 1.5-2.5cm (0.5-1in) from older wood.
Wall-trained shrubs trained to form a permanent branch framework against a wall or fence
Examples: Abutilon megapotamicum, Ceanothus, Fremontodendron.
Pruning: In early spring cut back flowered growths to two to four buds from the framework branches.