Species

Thuja occidentalisEastern Arborvitae Northern White Cedar

31 other cultivars

shrubN. America Native

Emerald Green Arborvitae

Thuja occidentalis 'Smaragd'

The Story

Plant Bio

Thuja occidentalis is a slow-growing, cold-hardy coniferous evergreen native to the wet soils and swamp borders of eastern and central North America. The species develops a conical crown of scale-like foliage arranged in flat, fan-like sprays and produces small, upright woody cones.

'Smaragd' is a compact, semi-dwarf cultivar that maintains a dense, narrowly pyramidal form without shearing. The glossy, bright emerald-green foliage retains its vibrant color throughout the winter months without browning.

Uses & Benefits:

Provides a neat, architectural, vertical accent with year-round emerald-green color that does not discolor in winter.

Functions as an excellent, low-maintenance privacy screen or windbreak that requires minimal pruning to maintain its shape.

Offers dense, year-round nesting cover, shelter, and roosting sites for songbirds and small mammals.

SpeciesThuja occidentalisEastern Arborvitae Northern White Cedar

Essentials

At a Glance

Plant Type

Shrub

Height

180"

Width

48"

Light

Full Sun, Partial Sun

Zones

4, 5, 6, 7

Water

Medium

Humidity

Moderate to High

Lifespan

Long

Native To

North America

Toxicity

Toxic if Ingested

Bloom period

Spring

In flower about 3 months of the year

Planting

How to Grow

Select a site in full sun to partial shade with moist, fertile, well-drained loamy soil.
Dig a hole twice as wide as the root ball and of equal depth, ensuring the root flare sits level with or slightly above the surrounding soil.
Backfill with native soil, tamp lightly to remove air pockets, and water deeply to settle the roots.
Apply a two- to three-inch layer of organic mulch in a wide ring around the base, keeping the mulch several inches away from direct contact with the trunk.

Pro Tip

Never prune back into the bare, brown interior wood, as this species lacks adventitious buds on old wood and cannot regenerate foliage to cover bare patches.

Keep It Thriving

Care Guide

Do

Water deeply every seven to ten days during dry summer periods to maintain consistent soil moisture.
Prune lightly in early spring before new growth begins if shaping a formal hedge.
Clear grass clippings and debris away from the trunk base to prevent fungal cankers.

Don't

Do not pile mulch directly against the trunk, which traps moisture and rots the bark.
Do not cut into old, leafless wood when pruning.
Do not plant in poorly drained, waterlogged, or heavily compacted soils.

Seasonal Care Calendar

Task	Jan	Feb	Mar	Apr	May	Jun	Jul	Aug	Sep	Oct	Nov	Dec
Fertilize
Mulch
Pest Check
Prune

Watch Out For

Pests & Diseases

Common Pests

Common Diseases

In the Garden

Landscape Uses & Companions

Landscape Uses

Privacy ScreenHedgeFoundation PlantingSpecimen/Focal PointWindbreak

Companion Plants

Physocarpus opulifolius Hydrangea arborescens Hemerocallis Echinacea purpurea

Multiply

Propagation Methods

Good to Know

Common Questions

Emerald Green Arborvitae questions

What zones can Emerald Green Arborvitae grow in?

Emerald Green Arborvitae is hardy in USDA Zones 4–7. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.

Is Emerald Green Arborvitae deer resistant?

Not reliably. Deer may browse Emerald Green Arborvitae, especially tender spring growth — plan on repellents or fencing where pressure is high.

When does Emerald Green Arborvitae bloom?

Emerald Green Arborvitae typically blooms in spring through spring. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.

Does Emerald Green Arborvitae need full sun?

Emerald Green Arborvitae does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.