Leyland cypress

Cupressocyparis leylandii

Fast-growing evergreen conifer hybrid (Monterey cypress × Nootka cypress) widely planted as a screen or windbreak. Capable of 1 m of growth per year in good conditions — both its strength and its principal management problem.

Hardiness ratings

Leyland cypress hardiness across the four zone systems
SystemRatingTemperature rangeHow to read it
USDA hardiness zone Zone 6–10 −23.3 °C to 4.4 °C Plant tolerates down to this zone
RHS hardiness rating H5 −15 °C to −10 °C Plant needs at least this level of cold tolerance
Canadian plant hardiness zone Zone 6–9 −18 °C and warmer Plant tolerates down to this zone
Australian (ANBG) zone Zone 2–6 −10 °C to 15 °C Plant tolerates down to this zone

Growing notes

  • Reaches 20 m in 20 years if unmanaged — capable of dense effective windbreak at any chosen height, but only if clipped regularly to keep that height
  • WARNING: Leyland cypress is the single most common neighbour-dispute hedge in the UK — falls under the Anti-Social Behaviour Act 2003 high hedges provisions if allowed to exceed 2 m and block neighbour light. Manage height proactively, do not plant in narrow boundary positions
  • Will not regenerate from bare wood — once cut back into brown growth, that side stays brown, plan height pruning before bare wood is exposed
  • Tolerates exposure, salt wind, and coastal conditions exceptionally well — for that reason still the standard agricultural shelter-belt species across the British Isles

Categories

Related plants

Cross-check Leyland cypress against your zones

Reference

Leyland cypress on Wikipedia