New hedges require formative pruning for their first couple of years after planting, which involves minor pruning to promote a good shape/ form as it turns into a more established hedge. Formative pruning is usually carried out in winter or early spring.  After this, maintenance trimming is carried out, usually once a year for informal hedges and twice a year for formal hedges.

Maintenance trimming is generally carried out between spring and summer. Timing of pruning should take into account the potential for nesting birds, and be delayed until after the nesting season - considered to run from March to August - if there are any signs that indicate activity.