How to Grow Leylandii
×Cuprocyparis leylandii
Leylandii is the fastest-growing conifer hedge in the UK, capable of adding up to 90 cm per year. Plant 60 cm apart for a dense evergreen screen. Clip 2-3 times per year from May to September to maintain shape — never cut into old brown wood as it will not regenerate. Tolerates most soils and positions from full sun to partial shade. Water well during the first two years of establishment. Once mature, it is drought-tolerant and virtually maintenance-free beyond regular trimming. Can reach over 20 metres if left unclipped, so start trimming from year one.
Yearly Lifecycle
Care Essentials
Balanced fertiliser in spring. Established hedges rarely need feeding unless growth is poor.
Watch For
- Cypress aphid
- Coryneum canker
- Pestalotiopsis dieback
Companions
Thuja, Yew, Beech, Holly
Track your Leylandii care schedule — pruning, feeding, and seasonal tasks
Start planning freeCare Requirements
☀️ Light
Full sun to partial shade; grows fastest in full sun
Thrives in full sun to partial shade. Growth rate is fastest in open sunny positions but tolerates shade well. Avoid deep shade where growth becomes thin and leggy.
💧 Watering
Water well in first 2 years; drought-tolerant once established
Water newly planted hedges regularly and deeply during the first two growing seasons, especially in dry spells. Once established, leylandii is very drought-tolerant and rarely needs supplemental watering.
🌱 Fertilizing
Feed in spring if growth is slow; established hedges rarely need it
Apply a balanced granular fertiliser in spring if growth appears sluggish. Established healthy hedges on reasonable soil rarely need feeding. Over-feeding promotes excessive growth requiring more frequent clipping.
✂️ Pruning
Clip 2-3 times May-September; never cut into old wood
Clip hedges in May, July, and optionally September. Always cut within the green growth zone — leylandii cannot regenerate from old brown wood. Maintain a slight taper with the base wider than the top.
Growing Tips
Never cut into old wood
Leylandii cannot regenerate from bare brown stems. Once you cut past the green growth, that section stays bare forever. Keep on top of regular trimming.
Start trimming young
Begin clipping from the first year of planting. This encourages dense branching from the base and prevents the hedge becoming thin at the bottom.
Maintain a taper
Keep the base wider than the top so sunlight reaches the lower branches. A flat-sided or top-heavy hedge will go bare at the base over time.
Height management
Under the Anti-social Behaviour Act 2003, neighbours can complain about hedges over 2 m. Keep to a manageable height from the start rather than trying to reduce a tall hedge later.
Pests & Diseases
Pest Cypress Aphid
Identification: Grey-brown aphids clustered on stems; dieback of inner foliage turning brown; sooty mould on honeydew deposits
- Encourage natural predators such as ladybirds and lacewings
- Prune out and destroy heavily infested branches in early spring
- Spray with pyrethrin-based contact insecticide if damage is severe and spreading
Disease Coryneum Canker Seiridium cardinale
Symptoms: Sunken cankers on stems and branches; resin bleeding from affected areas; branch dieback with foliage turning brown
Treatment: Prune out affected branches well below the canker; sterilise tools between cuts; destroy prunings
Prevention: Maintain plant vigour with adequate watering and feeding; avoid damage to bark from strimming or mowing
Disease Pestalotiopsis Dieback
Symptoms: Patches of brown foliage appearing randomly through the hedge; affected shoots die back from the tips; small black fruiting bodies visible on dead foliage
Treatment: Prune out affected growth back to healthy green tissue; improve air circulation within the hedge
Prevention: Avoid stress from drought or waterlogging; maintain regular clipping to promote good airflow; do not clip in wet weather
Spacing & Planting
| Plant spacing | 60 cm |
| Row spacing | 60 cm |
| Mature height | 1500 cm |
| Mature spread | 400 cm |
60 cm apart for dense hedging. For specimen trees, allow 300 cm.
Log Leylandii in your garden — track growth, care, and harvests year after year
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