How to Grow Western Red Cedar Atrovirens

Western Red Cedar Atrovirens

Thuja plicata 'Atrovirens'

tree

Western Red Cedar Atrovirens is a narrow, columnar evergreen conifer cultivar prized for its dense, dark green foliage and elegant upright form. It is a compact selection of the native Pacific Northwest cedar, ideal for screening, hedging, and ornamental plantings. This cultivar maintains excellent color year-round and grows at a moderate pace, reaching 20-40 feet tall but only 3-6 feet wide at maturity.

Growing Conditions

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Sun: Full sun to partial shade; 4-6 hours of direct sunlight daily for best color density

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Water: Moderate to consistent moisture; water deeply 2-3 times weekly during first growing season, then weekly during dry spells. Avoid waterlogging. Mulch to retain moisture and cool roots.

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Spacing: 36-60 inches

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Days to maturity: 3-5 years to landscape size

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Planting depth: Plant at same depth as root ball; top of root ball should be level with soil surface

Soil

Type: Moist, well-draining loamy or slightly acidic soil

pH: 5.5-7.0

Amendments:

Compost or aged bark mulch Peat moss for moisture retention Perlite or sand if drainage is poor

Growing Zones

Find your zone →

Thrives in zones 5-8, tolerates zones 4b-9a

4b 5a 5b 6a 6b 7a 7b 8a 8b 9a

Growth Stages

Establishment

First 12 months

Young transplant with actively growing roots and initial branch development

Water consistently but avoid waterlogging. Protect from harsh winds and hot afternoon sun in first season. Stake if necessary. Do not prune yet except to remove dead or crossing branches.

Active Growth

Years 2-4

Vigorous upward and outward growth, filling in lateral branches with dense foliage

Maintain consistent moisture. Apply 2-3 inches of mulch. Prune only to shape and remove diseased wood. Fertilize lightly in spring with balanced slow-release fertilizer if needed.

Maturation

Years 4-10

Tree reaches near-full height and width; columnar form becomes pronounced and dense

Reduce watering frequency once established (every 10-14 days unless drought). Selective pruning for shaping. Monitor for scale insects and spider mites in dry conditions.

Prime Ornamental

Year 10+ (indefinite)

Full-sized, dense columnar form with rich dark green color; minimal growth changes annually

Water during extended drought. Light pruning to maintain shape; avoid heavy cutting into old wood. Remove any diseased or dead branches promptly. No fertilizer typically needed.

Companion Planting

Plan your garden →

Plant with:

Juniperus scopulorum 'Skyrocket' Ilex crenata (Japanese Holly) Boxwood Ornamental grasses Hydrangea Rhododendron Azalea

Avoid planting near:

Salt spray areas (extremely tolerant but avoid direct coastal salt winds) Poorly drained wet areas Areas with heavy urban pollution

Common Pests

Increase humidity; spray with water to dislodge. Use horticultural oil or insecticidal soap in spring. Prune dense interior growth to improve air circulation.
Hand-pick and destroy bags in late fall or early spring before moths emerge. Spray with Bacillus thuringiensis (Bt) in early summer when caterpillars are young.
Spray with horticultural oil in dormant season or when crawlers are active. Prune heavily infested branches. Maintain tree vigor and avoid water stress.
Prune out infested tips; destroy prunings. Apply systemic insecticide in early spring when moths emerge. Maintain healthy growing conditions.

Uses

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Screening and Privacy Hedging

Household

The narrow, columnar form and dense foliage make Western Red Cedar Atrovirens an excellent choice for creating living screens and privacy barriers. Plant in single or double rows to create effective windbreaks and visual barriers. [source]

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Bird and Wildlife Shelter

Wildlife

Dense evergreen foliage provides year-round shelter, nesting sites, and cover for birds, squirrels, and other wildlife. The tree also produces small seed cones that birds feed on. [source]

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Aromatic Cedar Wood

Craft

Western Red Cedar wood is naturally aromatic with a pleasant, distinctive cedar scent. Branches and prunings can be dried and used in cedar chests, closets, or craft projects for their natural moth-repelling properties. [source]

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Culinary Cedar Flavor (Foliage)

Culinary

In small quantities, fresh or dried foliage can be used as a flavoring in teas, broths, and gourmet dishes, offering a unique citrusy, woody note. Use sparingly as the foliage contains volatile oils. [source]

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Traditional Herbal Medicine

Medicinal

Historically used by Pacific Northwest indigenous peoples and in traditional medicine for respiratory support and immune wellness. Modern herbalists use cedar leaf tea, though consultation with a healthcare provider is recommended. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

Not a harvest plant; this is an ornamental tree. Remove dead or diseased branches any time. Light shaping can be done in spring or early summer; avoid heavy pruning in late summer as it can damage winter hardiness.

Fun Facts

🌱 Western Red Cedar is not a true cedar (genus Cedrus) but rather a member of the Cupressaceae (cypress) family. The common name comes from the aromatic cedarwood scent of the heartwood.
🌱 The 'Atrovirens' cultivar name means 'dark green' in Latin, referring to its distinctly deep green color compared to the species type, which can appear somewhat grayish or yellowish in winter.
🌱 Western Red Cedar has been culturally significant to Pacific Northwest tribes for over 2,000 years, used for everything from canoes and totem poles to clothing and shelter—earning it the nickname 'Tree of Life.'

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