Hedges can be divided into three groups:
Group 1 - Upright plants
For example: deciduous (hawthorn, privet); evergreen (box, Escallonia, Lonicera nitida)
- Cut back plants to 15-30cm (6in-1ft) on planting
- In summer trim side branches lightly to encourage bushing out
- In the second year (February to March) cut back growth by half
- Throughout the second summer trim side branches to maintain sides that taper towards the top
- In the second autumn cut the topmost branch (‘leading shoot’) to the desired hedge height
- Cut back all stems by one-third after planting
- Repeat this at the same time next year
Annually, during May to September, trim back the top and sides every four to six weeks to maintain the desired shape.
Group 2 – Stocky deciduous plants, naturally bushy at the base
For example: beech, hornbeam, hazel, Forsythia and Ribes sanguineum
- On planting, cut back leading shoots and side shoots by one-third, cutting to a well placed bud
- Repeat this in the second winter to prevent straggly growth and thicken up the hedge base
Trim annually in June (or after flowering) and again in August, clip to a shape that tapers at the top.
Group 3 - Conifers and most evergreens
For example: Lawson cypress, Leyland cypress, yew, bay, cherry laurel, cotoneaster and pyracantha
- On planting, leave the leading shoot unpruned, lightly cutting back any straggly side shoots
- In summer, trim sideshoots and tie in the leader to a supporting cane as it grows
- Use secateurs for broad-leaved evergreens (e.g. laurel and bay)
Clip to the desired shape one to three times during summer, until late August, when trimming should cease to reduce the risk of bare patches (see problems below). Use secateurs or hand shears for broad-leaved evergreens (e.g. laurel and bay). Stop the leading shoot at the desired height. Most conifers will not re-grow from old wood, so avoid hard pruning.