Thuja plicata
western red cedar
A large, evergreen, narrowly-pyramidal tree reaching an ultimate height of up to 35m. Aromatic, glossy, scale-like, sharply-pointed mid to dark green leaves are held in large drooping sprays on spreading branches that curve upwards at the end. Cones are egg-shaped and around 1.3cm long
Other common names
British Columbia cedarCalifornian white cedar
see moregiant arbor-vitae
Nootka Sound arbor-vitae
western arbor-vitae
yellow cypress
Synonyms
Thuja giganteaThuja lobbii
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Size
Ultimate height
Higher than 12 metresTime to ultimate height
10–20 yearsUltimate spread
Wider than 8 metresGrowing conditions
Moisture
Moist but well–drained, Well–drainedpH
Acid, Alkaline, NeutralColour & scent
| Stem | Flower | Foliage | Fruit | |
| Spring | Green | |||
|---|---|---|---|---|
| Summer | Green | |||
| Autumn | Green | |||
| Winter | Green |
Position
- Full sun
- Partial shade
Aspect
North–facing or West–facing or South–facing or East–facing
Exposure
Exposed or Sheltered Hardiness
H6Botanical details
- Family
- Cupressaceae
- Native to GB / Ireland
- No
- Foliage
- Evergreen
- Habit
- Columnar upright
- Potentially harmful
- Harmful if eaten, skin allergen. Wear gloves and other protective equipment when handling
- Genus
Thuja are fast-growing evergreen trees of narrowly conical habit, with flat sprays of tiny, aromatic, scale-like leaves and small knobbly cones
- Name status
Correct
- Plant range
- W North America
How to grow
Cultivation
Grow in moist but well-drained soil in full sun with shelter from cold, drying winds. See conifer cultivation for further advice
Propagation
Propagate by semi-ripe cuttings in late summer; propagate by seed in late winter in containers in a cold frame
Suggested planting locations and garden types
- Architectural
- Low Maintenance
- Hedging and screens
Pruning
No pruning required; trim in spring and late summer if grown as a hedge
Pests
May be susceptible to scale insects and conifer aphid
Diseases
May be susceptible to diseases including honey fungus, Phytophthora root rot and thuja blight. See conifers: brown patches for further advice
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