How to Grow Western Red Cedar (Thuja plicata)

Western red cedar (Thuja plicata) is a tall-growing conifer that originates from western regions of North America. In UK gardens Western red cedar is a popular choice for medium to tall garden hedges as the rich, dark, glossy evergreen foliage has a moderately fast rate of growth and responds well to trimming. The variety commonly grown for hedging is Thuja plicata ‘Atrovirens’. There are other varieties of Thuja plicata, which are slower-growing and more compact in size, suitable to plant as single specimens or smaller hedges.

The leaves of Thuja plicata are scale-like, borne in flat sprays, and give off an aromatic, pineapple-like scent when crushed. Allowed to grow naturally, western red cedar forms a tall, conical-shaped tree that can reach up to 35m high. The branches are slightly drooping and made up of mid-green, scale-like leaves. Clusters of small flattened oval brown cones, up to 1.3cm long, are borne in summer and autumn.

Thuja plicata and Thuja plicata ‘Atrovirens’ have moderately fast growth of 45-60cm a year. Regular trimming keeps a western red cedar hedge compact, restricting growth to as little as 1.5-2m high. Left untrimmed it forms a tall-growing and broadly columnar tree with a mature height of around 35m with a spread of around 7-10m. The oldest known western red cedar tree grows in the US and is over 60 metres tall and 15 metres wide. Compact-growing varieties are slower-growing and much smaller, typically reaching around 2.5m high and 1.5m wide.

Western red cedar hedges and mature trees provide good nesting sites for birds and shelter for wildlife.

Grow western red cedar in sun or shade in good,