How to Grow Techny's Emerald Western Red Cedar
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Techny's Emerald Western Red Cedar
Thuja occidentalis 'Techny's Emerald'
treeTechny's Emerald is a narrow, columnar evergreen conifer prized for its dense, vibrant green foliage and winter hardiness. This cultivar is a sport of the 'Techny' variety, selected for superior color retention and hardy performance in cold climates. It grows into a tight, columnar form ideal for screening, windbreaks, and formal hedging.
When should you plant Techny's Emerald Western Red Cedar in your zone?
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Example Techny's Emerald Western Red Cedar timeline · Pittsburgh, PA (Zone 6b)
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Plant Techny's Emerald Western Red Cedar
Around Apr 17Near Pittsburgh's average last spring frost.
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Tend & protect
Late spring–summerWatering, feeding, and pest-watch reminders.
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Harvest Techny's Emerald Western Red Cedar
Late summer into fallBefore the first fall frost (≈ Nov 8)
Sample dates for Pittsburgh, PA. Sign up to get exact Techny's Emerald Western Red Cedar dates for your own zip code.
Growing Conditions
Soil
Growing Zones
Find your zone →Exceptionally hardy; thrives in zones 2-7, with outstanding cold tolerance to -40°F
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Get my Techny's Emerald Western Red Cedar timeline →Growth Stages
Establishment
Year 1Young plant with delicate feathery foliage, narrow columnar form evident from planting
Water deeply 2-3 times weekly during first growing season. Mulch base 2-3 inches. Avoid transplant shock by planting in spring or early fall.
Root Development
Years 2-3Tree is establishing root system; foliage remains vibrant emerald green, vertical growth accelerates
Continue consistent watering. Apply balanced evergreen fertilizer in spring. Mulch to retain soil moisture and regulate temperature.
Vegetative Growth
Years 4-10Tree grows 12-18 inches annually, developing dense interior foliage and characteristic narrow columnar silhouette
Prune in early spring if needed to maintain shape. Thin crowded interior growth for air circulation. Reduce watering frequency as roots deepen.
Maturity
Year 10+Tree reaches mature height (typically 15-20 feet) with full, dense emerald foliage; maintains columnar form with minimal growth
Minimal pruning required. Light fertilizing optional in spring. Monitor for pest/disease issues. Mulch to maintain soil health.
Companion Planting
Plan your garden →Plant with:
Avoid planting near:
Common Pests
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Prune and remove infested foliage; apply insecticidal soap in May-June; maintain plant vigor through proper watering
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Increase humidity with water spray; apply miticide if severe; ensure proper drainage to avoid stress
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Prune affected branches; apply horticultural oil in dormant season; beneficial predators control populations
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Hand-pick bags in fall/winter; apply Bt (Bacillus thuringiensis) in early summer; prune infested branches
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Install deer fencing or use deer repellent sprays; less palatable than some arborvitae but still browsed in harsh winters
Uses
Evergreen Arrangements & Winter Décor
HouseholdThe vibrant emerald foliage remains colorful through winter and holds water well in cut arrangements. Branch material is prized for holiday wreaths, garland, and fresh floral displays. [source]
Privacy Screening & Windbreak
HouseholdThe narrow, dense columnar form creates an excellent living hedge and windbreak with minimal space footprint. Reaches 15-20 feet tall while staying only 3-5 feet wide. [source]
Bird & Wildlife Shelter
WildlifeDense evergreen foliage provides year-round cover and nesting sites for songbirds, small mammals, and insects. Branches offer roosting perches and protection from predators. [source]
Traditional Herbal Use (Thuja Occidentalis)
MedicinalThuja species have been used in traditional herbalism and homeopathy, though scientific evidence is limited. The essential oil contains thujone and is used cautiously in some traditional remedies. [source]
Aromatic Wood & Fragrant Foliage
CraftThe foliage releases a pleasant, distinctive aromatic scent when brushed or crushed, making it appealing for sensory gardens and landscape design. [source]
This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.
Harvest Tips
This ornamental tree is not harvested for food or traditional material harvest. However, foliage can be clipped for fresh evergreen arrangements and floral design in winter. Cut branches in late fall after frost for best color and longevity.
Fun Facts
- 🌱 Techny's Emerald was selected from the 'Techny' cultivar, which was developed at the Chicago Botanic Garden and named after the Techny Benedictine Monastery in Illinois, reflecting its extreme cold hardiness.
- 🌱 Western Red Cedar (Thuja occidentalis) is not actually a true cedar but a member of the cypress family; it was misnamed by early European settlers who confused it with true cedars of the genus Cedrus.
- 🌱 This cultivar's narrow columnar form can save up to 60% of space compared to traditional spreading evergreens while providing equivalent screening and windbreak function.
Gardening Terms
New to gardening? Learn about terms used in this guide:
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