The Leyland cypress (× Cuprocyparis leylandii) is a fast-growing, effective hedge or screen that’s widely popular for its privacy-enhancing properties. However, without regular pruning, it can become unmanageable, leading to shading, soil dryness, and difficulties in maintaining neighboring plants. Proper pruning is essential to control its size and maintain its health, ensuring a balanced garden environment.
When to Prune Leyland Cypress
Pruning should be done during the active growing season, typically from April to the end of August. Depending on your local climate, up to three cuts may be needed to maintain the hedge. Before starting, check for bird nests, as damaging or destroying active nests is an offense under the Wildlife & Countryside Act 1981.
How to Prune Leyland Cypress
Formative Pruning for Young Hedges
- Year One: In April, trim back long side shoots to encourage dense growth. Lightly trim the sides again in July, tying the leading shoot to a support cane for vertical growth.
- Year Two: Continue trimming the side shoots to promote a tidy, compact hedge. Allow the plant to maintain a neat appearance through winter.
- Subsequent Years: Avoid cutting the top until the hedge reaches the desired height. Once the height is achieved, shorten the leading shoots by 15 cm (6 in) below the required height in spring to allow new growth to fill in the top.
Pruning Established Hedges
- Trim both the top and sides up to three times during the growing season.
- Shape the hedge into an inverted wedge (flat-topped A-shape) to allow light to reach all parts of the hedge evenly, preventing the base from becoming brown and bare.
Managing Overgrown Hedges
Leyland cypress can quickly become overgrown without regular maintenance. For overgrown hedges:
- Reduce the height by up to one-third in early April, just before new growth begins.
- Avoid excessive cutting at once, as taking too much off the top can leave a bare or flat-topped hedge, or even kill older, weaker plants.
- If a reduction of more than one-third is essential, do it in stages: reduce by one-third initially, allow recovery, and then trim the remainder.
- When reducing width, avoid cutting into old, leafless wood, as Leyland cypress does not regenerate from bare branches.
Addressing High Hedges
Unpruned Leyland cypress can become a nuisance, towering over gardens and affecting sunlight and soil. High hedge issues have been addressed under Part 8 of the Anti-Social Behaviour Act 2003, effective from June 2005. This legislation allows homeowners affected by excessively tall hedges to seek solutions without legal battles, improving the enjoyment of their property.