Cupressocyparis (× Cuprocyparis)

Cupressocyparis

A small group of tall, fast-growing, evergreen conifers often used for quick hedging. The most well known hybrid is leylandii, originating at Leighton Hall, Welshpool, Wales.

Family: Cupressaceae
Botanical Name: Cupressocyparis (× Cuprocyparis leylandii, Cupressus x leylandii)

Common Names: Leyland cypress, false cyprus

Foliage: Evergreen, tiny scale-like leaves in dense sprays.

Cones: small spherical.

Soil: Moist but well-drained soil (chalk, clay, sand or loam). Acid, alkaline or neutral pH.

Conditions: Full sun, any aspect.

Habit: Tall upright, narrowly conical or columnar.

Type: Very large tree.

Toxicity: Foliage can irritate skin. Wear gloves and wash hands after handling.

Hardiness: Fully hardy in the UK.

Planting and Growing Cupressocyparis

Plant root balled specimens from September to November. Plant pot-grown types in spring to allow them to establish.

Widely planted in large gardens. Not recommended for small or medium size gardens as it can quickly become a nuisance. Often grown as a fast growing hedge, it makes a good windbreak but will need regular pruning to keep it in check.

Taking Care of Cupressocyparis

Water well in dry weather for first year until established.

Pruning Cupressocyparis

Regular trimming (two or three times a year) of young, green shoots is necessary to keep hedges neat and growth in check. Will not regenerate if old wood is pruned into.

Pests and Diseases

Can be affected by conifer aphid and scale insects. Prone to a bacterial canker and honey fungus.

Propagating Cupressocyparis

Take three inch semi-hardwood cuttings in late summer and root in sand with a little bottom heat.

Varieties of Cupressocyparis

× Cuprocyparis leylandii (Leyland cypress) is an extremely vigorous columnar conifer, with grey green foliage. Often used as a fast growing, tall hedge. Although useful as a fast-growing plant, it will continue growing at a fast pace once it has reached its intended height and can quickly develop into a large tree if left unclipped. Growth can be up to 3ft (90cm) a year. Mature height to 100ft (30m) or more. Cultivars include:

  • 'Leighton Green' has bright green foliage, with round, brown female cones and ovoid, yellow male cones.
  • 'Haggerston Grey' (blue leyland cypress) is a fast growing tree with blue-green foliage.
  • 'Castlewellan' a beautiful yellow-green tree that is less vigorous.