Thuja plicata / Western Red Cedar

Description

Common Name: Western Red Cedar Hedge, Giant Arborvitae
Botanical Name: Thuja plicata
Plant Type: Evergreen conifer hedge
Mature Height: 2-5m (as hedge)
Mature Spread: 80cm-1.2m (hedge width)
Flowering Period: April-May (inconspicuous)
Flower Colour: Yellowish-brown (small cones)
Foliage: Rich green scale-like leaves with bronze winter tints, evergreen
Hardiness: RHS H7 (very hardy throughout UK and Ireland)
Soil Requirements: Moist, well-drained soil, tolerates various conditions
Aspect: Full sun to partial shade
Maintenance: Low to moderate (1-2 trims per year)

Description

Like majestic walls of ancient forest grandeur, Thuja plicata hedging brings exceptional scale and natural beauty to gardens with its magnificent rich green foliage that transforms to warm bronze tones in winter, creating one of the most impressive and fast-growing evergreen hedges for Irish landscapes. This distinguished conifer hedge embodies the wild majesty of North American forests with its vigorous growth habit that forms substantial, dense barriers whilst offering the extraordinary characteristic of aromatic foliage that releases a delightful cedar fragrance when brushed against or trimmed.

Each perfectly formed hedge displays the most exquisite scale-like foliage in lustrous rich green that creates beautiful textural interest with its naturally glossy surface and elegant layered branching pattern. The remarkable seasonal colour variation adds winter interest with subtle bronze tinting that warms the garden during the coldest months, whilst the rapid growth rate ensures quick establishment and impressive screening that transforms garden boundaries in just a few seasons.

The exceptional vigour and adaptability make Western Red Cedar hedging equally valuable in large-scale landscape projects and substantial garden settings, thriving in Irish conditions whilst tolerating a wide range of soils including clay and slightly acidic conditions. This supremely hardy variety withstands harsh weather, coastal winds, and challenging sites whilst maintaining excellent density and form, making it one of the most reliable and impressive large-scale hedging plants for Irish gardens requiring substantial screening.

Beloved by gardeners seeking dramatic impact and rapid results, plicata combines outstanding ornamental presence with exceptional practical benefits and remarkable longevity. Plant to create substantial garden boundaries that provide impressive year-round screening, use as windbreak hedging in exposed locations, or establish as backdrop plantings that will provide privacy, shelter, and forest-like grandeur for generations to come with excellent value for money.

Caragh’s Garden Notebook

Plant in autumn or early spring in well-prepared soil with good drainage, though Western Red Cedar tolerates a wide range of soil conditions including clay and slightly acidic soils. Choose a position with good air circulation and space for the substantial mature size, allowing adequate room for the hedge’s impressive width. Space plants 80cm-1m apart in a single row for dense coverage and optimal screening.

Maintain soil fertility with annual mulching using organic matter such as compost or bark chips applied in spring around the hedge base. Water regularly during the first growing season and during dry spells to establish strong root systems, as consistent moisture promotes rapid growth and maintains healthy foliage colour.

Trim 1-2 times per year (late spring and again in late summer if needed) to maintain shape and control the vigorous growth, using sharp hedge trimmers to preserve the aromatic foliage. The fast growth rate means regular trimming is important to maintain desired size, whilst the naturally dense habit responds well to shaping and formal training.

Feed established hedges with general purpose or evergreen fertiliser in early spring to promote vigorous growth and maintain the rich green colouring, though Western Red Cedar performs well even without regular feeding once established. The substantial size means this hedge is best suited to larger gardens with adequate space for its impressive mature dimensions.

Water regularly during dry periods, particularly in the first two years after planting, as consistent moisture promotes the rapid growth that makes this hedge so valuable for quick screening. The extensive root system adapts well to most conditions once established, though mulching helps retain moisture and suppress weeds around the substantial hedge base.