How to Grow Emerald Arborvitae

Wikimedia Commons

Emerald Arborvitae

Thuja occidentalis 'Emerald'

tree

Emerald Arborvitae is a narrow, columnar evergreen conifer prized for its vibrant emerald-green foliage year-round and compact growth habit. It grows as a dense, upright tree with soft, feathery foliage that maintains its rich color even in winter, making it an excellent choice for screening, windbreaks, and ornamental landscaping. This cultivar is a superior selection of Eastern Arborvitae, offering better cold hardiness and disease resistance than many traditional varieties.

When should you plant Emerald Arborvitae in your zone?

Get a personalized planting timeline — when to start seeds, transplant, and harvest — based on your USDA zone and local frost dates. Free to start.

Get my Emerald Arborvitae timeline →

Example Emerald Arborvitae timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Emerald Arborvitae

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Emerald Arborvitae

    Late summer into fall

    Before the first fall frost (≈ Nov 8)

Sample dates for Pittsburgh, PA. Sign up to get exact Emerald Arborvitae dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun to partial shade, 6+ hours of direct sunlight daily for optimal color and density
💧
Water: Moderate watering; keep soil consistently moist but not waterlogged. Water deeply after planting for the first year. Once established, trees are fairly drought-tolerant but perform best with regular moisture. Water less in winter.
📏
Spacing: 24-36 inches apart for screening purposes; allow 12-18 inches for compact single specimens inches
📅
Days to maturity: 3-5 years to reach ornamental maturity; continues growing for 20+ years
🌱
Planting depth: Plant at same depth as root ball; top of root ball should be level with or slightly above ground

Soil

Type: Well-draining loamy or slightly acidic soil
pH: 5.5-7.0
Amendments:
Peat moss or compost at planting Mulch layer 2-3 inches deep Perlite or sand if soil is heavy clay

Growing Zones

Find your zone →

Thrives in zones 2-8, with best performance in zones 3-7

2a 2b 3a 3b 4a 4b 5a 5b 6a 6b 7a 7b 8a

Sign up free to see if Emerald Arborvitae grows in your zone — and get a personalized planting timeline.

Get my Emerald Arborvitae timeline →

Growth Stages

1

Establishment (Year 1)

12 months

Young tree focuses on root development with modest above-ground growth. Foliage is emerald green but growth is relatively slow as energy goes belowground.

Water regularly to keep soil moist. Mulch heavily. Avoid fertilizing excessively. Prune only to remove dead branches. Stake if planted in windy location.

2

Vegetative Growth (Years 2-3)

24 months

Tree enters period of steady vertical and lateral growth, becoming more columnar and dense. Foliage deepens in color and fills in nicely.

Continue regular watering, especially during dry spells. Light pruning to maintain shape is acceptable. Reduce mulch as tree establishes. Monitor for spider mites in dry conditions.

3

Mature Form (Years 3-5)

24 months

Tree reaches its characteristic narrow, columnar shape with dense emerald foliage throughout. Typically 12-15 feet tall and 3-4 feet wide at maturity.

Water during extended droughts. Prune minimally to maintain natural shape. Remove any winter damage in spring. Apply balanced fertilizer if needed.

4

Established Tree (Year 5+)

Indefinite (20-40 year lifespan)

Fully mature tree maintaining its narrow columnar form with vibrant emerald-green color year-round. Minimal growth, primarily maintenance phase.

Water only during drought. Light spring pruning acceptable. Remove any dead or diseased branches promptly. Watch for spider mites and bagworms, especially in stressed trees.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Black Walnut (toxic juglone) Other densely-branching evergreens that compete for space Areas with poor air circulation prone to fungal disease

Common Pests

  • Prune out infested branches; apply insecticidal soap or neem oil in spring; use Bacillus thuringiensis (Bt) for bagworms

  • Increase humidity with regular misting; use miticide spray if severe; ensure adequate water in hot, dry weather

  • Prune out heavily infested branches; apply horticultural oil spray in early spring before growth starts

  • Ensure excellent drainage; avoid waterlogging; remove affected trees; improve soil drainage with amendments

Uses

🏠

Screening & Privacy Hedges

Household

Emerald Arborvitae's narrow, dense columnar form makes it ideal for creating natural privacy screens, windbreaks, and living barriers. Its compact width (3-4 feet) requires minimal space while providing excellent coverage. [source]

🌿

Year-Round Landscape Color

Ornamental

The tree maintains its rich emerald-green color throughout all four seasons, providing consistent visual interest when deciduous plants are bare. Especially valuable in winter landscapes. [source]

🦋

Wildlife Shelter & Nesting

Wildlife

Dense foliage provides excellent shelter and nesting sites for birds and small wildlife. The structure offers protection from predators and harsh weather. [source]

🏠

Foundation Plantings

Household

Its narrow columnar form is perfect for flanking entryways, framing windows, and creating vertical interest in foundation plantings without overwhelming the space. [source]

🎨

Floral Arrangements & Greenery

Craft

Branches can be cut for fresh floral arrangements and wreaths, offering elegant green foliage that holds well in water for several weeks. [source]

Harvest Tips

This is an ornamental tree, not harvested for consumption. Prune selectively in early spring to remove winter damage or maintain shape. Avoid heavy pruning into old wood, which may not regenerate. Cuttings can be propagated in summer using rooting hormone.

Fun Facts

  • 🌱 Emerald Arborvitae was selected in 1950 in Denmark and is botanically known as 'Emerald' or 'Smaragd,' and it maintains its color significantly better than older arborvitae varieties even in harsh winter conditions.
  • 🌱 The name 'arborvitae' means 'tree of life' in Latin, reflecting the tree's historical importance in Indigenous cultures and its use in traditional medicine.
  • 🌱 Unlike many arborvitae varieties that brown or discolor in winter, Emerald maintains its vibrant color year-round due to superior cold hardiness genes, making it a modern improvement over classic varieties.

Gardening Terms

New to gardening? Learn about terms used in this guide:

Join 30,000 gardeners planning their gardens with LizPlants.

Get your personalized Emerald Arborvitae planting timeline

Tell us your zip code and we'll calculate exactly when to start Emerald Arborvitae seeds, transplant seedlings, and harvest — based on your USDA zone and local frost dates. Includes calendar reminders and printable task lists. Free to start.

Get my Emerald Arborvitae timeline →