How to Grow Emerald Cone Arborvitae

Wikimedia Commons

Emerald Cone Arborvitae

Thuja occidentalis 'Emerald Cone'

shrub

Emerald Cone Arborvitae is a narrow, columnar evergreen shrub prized for its dense, vibrant green foliage that maintains color throughout winter. This compact cultivar grows in a tight, upright form, making it ideal for screening, borders, and accent plantings in landscapes. It is a relatively new introduction that combines the classic arborvitae appeal with improved cold hardiness and disease resistance.

When should you plant Emerald Cone 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 Cone Arborvitae timeline →

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

  1. Plant Emerald Cone 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 Cone Arborvitae

    Late summer into fall

    Before the first fall frost (≈ Nov 8)

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

Growing Conditions

☀️
Sun: Full sun to partial shade, 6-8 hours of direct sunlight daily for best color and density
💧
Water: Moderate water needs; water deeply after planting and during establishment (first 1-2 years). Once established, water during dry spells or prolonged drought. Avoid waterlogged soil, which can cause root rot.
📏
Spacing: 24 inches
📅
Days to maturity: 2-3 years to reach mature landscape form
🌱
Planting depth: Plant at same depth as root ball; do not bury stem

Soil

Type: Well-draining loamy to sandy loam soil
pH: 6.0-7.5
Amendments:
Peat moss or compost for moisture retention Perlite or coarse sand for drainage Mulch (2-3 inches) to moderate soil temperature

Growing Zones

Find your zone →

Thrives in zones 3-8, with exceptional cold hardiness down to -40°F

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

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

Get my Emerald Cone Arborvitae timeline →

Growth Stages

1

Establishment

1-2 months after planting

Newly planted shrub with developing root system; foliage may appear slightly stressed or dull

Water consistently to keep soil moist but not saturated. Avoid heavy pruning. Mulch around base to conserve moisture and regulate temperature.

2

Active Growth

Spring and early summer

Vibrant green foliage fills in; columnar form becomes more pronounced; new growth appears lighter green at branch tips

Continue regular watering during dry periods. Light pruning can shape form. Monitor for pests and diseases.

3

Hardening Off

Late summer through fall

Growth slows as temperatures cool; foliage may deepen in color and become more rigid in preparation for winter

Reduce watering frequency as growth slows. Do not fertilize late in season. Ensure good drainage to prevent ice damage.

4

Winter Dormancy

November through March (varies by zone)

Minimal visible growth; foliage maintains vibrant green color, though some cultivars may show slight bronze tinting in severe cold

No active watering needed in most regions. Provide windbreak protection in extremely windy sites. Snow/ice can damage branches; gently brush off heavy snow.

5

Year-Round Maintenance

Ongoing after establishment

Mature shrub maintaining columnar form and dense evergreen foliage throughout growing seasons

Annual light pruning to maintain shape (late winter/early spring). Fertilize in spring with balanced or slow-release fertilizer. Monitor for spider mites and bagworms.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Apple trees (susceptible to similar diseases) Pear trees Hawthorn (rust fungus vector) Wetland plants (requires better drainage than bog species) Heavily salt-treated areas

Common Pests

  • Spray with water to dislodge; use horticultural oil or neem oil in spring and summer; ensure adequate moisture to stress mites

  • Hand-pick bags in late fall or winter; spray with Bacillus thuringiensis (Bt) in early summer when larvae emerge

  • Apply systemic insecticide in early spring; prune out infested branch tips; maintain plant vigor

  • and

    Dormant oil spray in late winter; horticultural oil during growing season; improve air circulation

Uses

🏠

Privacy Screening & Windbreaks

Household

The dense, columnar form makes Emerald Cone ideal for creating living screens, hedges, and windbreaks in residential landscapes. Multiple plants create effective visual barriers and noise reduction while requiring minimal space. [source]

🎨

Holiday Decorations & Greenery

Craft

Fresh foliage can be harvested for wreaths, garlands, and floral arrangements, especially during fall and winter holidays. The vibrant green color and aromatic needles add festive appeal to seasonal decorations. [source]

🏠

Ornamental Landscaping & Accent Plants

Household

With its striking columnar shape and year-round color, Emerald Cone serves as an excellent accent plant for foundation plantings, entry gardens, and formal landscapes. It adds vertical interest and structure to garden designs. [source]

🦋

Wildlife Habitat & Shelter

Wildlife

Dense arborvitae foliage provides shelter, nesting sites, and cover for birds and small mammals throughout the year. The plant offers protection from predators and winter weather. [source]

💊

Traditional Herbal Uses

Medicinal

Arborvitae has been used in traditional medicine and herbalism for respiratory support and immune function. However, use should be cautious and under professional guidance, as some preparations can be toxic in large amounts. [source]

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

Harvest Tips

Emerald Cone Arborvitae is an ornamental shrub and is not harvested for fruit or produce. However, foliage can be lightly pruned for fresh greenery in floral arrangements or wreaths from late fall through early spring. Prune no more than 30% of the plant at one time, and always prune to lateral branches to encourage dense regrowth. Light shearing in late winter/early spring maintains the columnar form.

Fun Facts

  • 🌱 Emerald Cone Arborvitae is a newer cultivar that was developed to combine the excellent winter color retention of the species with superior disease resistance and compact form, making it an improvement over older arborvitae varieties.
  • 🌱 The name 'arborvitae' means 'tree of life' in Latin, and the plant has been valued by Indigenous peoples and early European settlers for its medicinal properties and practical uses in building and crafting.
  • 🌱 Emerald Cone is exceptionally cold-hardy and can survive temperatures as low as -40°F (-40°C), making it one of the most reliable evergreen shrubs for extreme winter climates.

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 Cone Arborvitae planting timeline

Tell us your zip code and we'll calculate exactly when to start Emerald Cone 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 Cone Arborvitae timeline →