Emerald Green arborvitae (Thuja occidentalis ‘Smaragd’) is one of the most popular and widely planted evergreen shrubs in North American horticulture, and it has earned that status through a combination of qualities that are genuinely hard to find in a single plant. It’s dense, tidy, naturally narrow, and exceptionally uniform in form. It holds its rich emerald-green color through winter without the bronzing that plagues so many other arborvitaes in cold weather. It grows at a manageable pace, requires virtually no shearing to maintain its shape, and fits comfortably into a wide range of landscape situations from foundation plantings to privacy screens. If you need a reliable, attractive, low-maintenance evergreen that does exactly what you expect it to do year after year, Emerald Green arborvitae is a plant that consistently delivers.

A cultivar of Eastern arborvitae, which is native to eastern North America, ‘Smaragd’ was developed in Denmark in the 1950s and introduced to the horticultural trade under the name “Smaragd,” the Danish and German word for emerald. It’s hardy in USDA zones 3 through 8, giving it one of the broadest cold-hardiness ranges of any popular landscape evergreen. It thrives in full sun, where it develops its densest habit and best color, but it tolerates part shade reasonably well, though plants in shadier conditions tend to be somewhat looser in form and less uniformly green. It prefers moist, well-drained soil with a neutral to slightly alkaline pH between 6.0 and 8.0, and it’s notably adaptable to clay soils as long as drainage is adequate. It doesn’t perform well in consistently dry or droughty conditions, which is one of its primary limitations compared to more drought-tolerant evergreens.

Emerald Green arborvitae is a narrowly columnar evergreen shrub with flat, fan-like sprays of scale-like foliage in a deep, glossy emerald green that remains reliably vivid through winter, which is one of its most valuable distinguishing traits among arborvitae cultivars. It grows slowly to moderately, typically adding 3 to 6 inches per year, and reaches a mature height of 10 to 15 feet with a spread of only 3 to 4 feet. This slender, upright profile is precisely what makes it so useful in the landscape: it provides significant vertical presence and screening without consuming large amounts of horizontal space. It produces small, oblong cones that are ornamentally inconsequential. It’s not edible. Deer resistance is unfortunately one of its weaknesses; arborvitae is a preferred browse plant for white-tailed deer, and in areas with moderate to heavy deer pressure, Emerald Green arborvitae can be severely damaged without protective measures. In the landscape, it’s most commonly used as a privacy screen or living fence, a windbreak, a foundation planting, a formal or informal hedge, a specimen accent plant, or a container evergreen for patios and entryways.

Plant care

Emerald Green arborvitae is a straightforward, undemanding shrub in the right site, but it does have specific preferences for moisture and sun that are worth respecting for the best long-term results. Proper planting, consistent care during establishment, and a few seasonal practices will keep it dense, green, and healthy for many years.

Watering

Consistent moisture is one of the most important factors in growing Emerald Green arborvitae successfully. During the first two to three growing seasons, water newly planted shrubs deeply and regularly to encourage deep root development. Allow the soil to dry slightly between waterings, but don’t let plants go into prolonged drought stress during establishment. Unlike many evergreens, arborvitae is not particularly drought tolerant, and dry conditions are one of the most common causes of browning foliage and general decline. In summer heat, established plants in average soils may still benefit from supplemental watering during extended dry spells, particularly in the first several years. Winter drought is also a genuine concern; arborvitae can suffer from desiccation damage when the foliage loses moisture on warm or windy winter days while the frozen ground prevents root uptake. A thorough, deep watering in late fall before the ground freezes is one of the most useful things you can do to prevent winter browning.

Fertilizing

Emerald Green arborvitae doesn’t need heavy feeding and grows acceptably in average garden soils without routine fertilization. If growth seems slow or foliage color is lackluster, a light application of a balanced slow-release fertilizer or one formulated specifically for evergreens in early spring is appropriate. Avoid fertilizing after midsummer, as this encourages tender new growth that won’t harden off properly before frost, increasing the risk of winter damage. In alkaline soils above pH 7.5, minor nutrient deficiencies, particularly iron and manganese, can cause yellowing between the leaf scales; an acidifying fertilizer or soil amendment may help in those situations. A soil test is the most reliable way to determine whether fertilization or pH adjustment is genuinely needed.

Pruning

One of Emerald Green arborvitae’s most appealing qualities is that it maintains its neat, columnar form with little to no pruning under normal circumstances. In most situations, the most you’ll need to do is remove any dead, brown, or damaged branches as they appear. If you’re growing it as a formal hedge and want a perfectly uniform face, a light shearing in late spring after the flush of new growth has extended is appropriate; avoid cutting back into old wood without foliage, as arborvitae doesn’t regenerate from bare wood the way broadleaf shrubs do. Never remove more than one-third of the green foliage in a single pruning session. If a branch is damaged by snow or ice and splays outward from the main form, it can be tied back gently or removed cleanly at its origin. Keep pruning tools sharp and clean to make clean cuts that heal efficiently.

Mulching

Mulching is especially beneficial for Emerald Green arborvitae because it directly addresses the tree’s greatest vulnerability, which is moisture stress. Apply a 3- to 4-inch layer of shredded bark or wood chip mulch in a ring around the base of each plant, extending out to the drip line, and keep the mulch pulled back 3 to 4 inches from the trunk to prevent moisture-related crown rot. Mulch conserves soil moisture, moderates temperature fluctuations at the root zone, suppresses competing weeds and turf grass, and gradually improves soil structure. In a row planting used as a privacy screen, mulching the entire bed rather than individual rings is both more effective and more attractive. Refresh the mulch layer each spring as needed to maintain adequate depth.

Dealing with deer

Deer browsing is one of the most serious practical challenges with Emerald Green arborvitae, particularly in suburban and rural areas with significant white-tailed deer populations. Deer are strongly attracted to arborvitae and can cause severe, disfiguring damage in a single night, especially in winter when other food sources are scarce. The most reliable protection for smaller plants is physical exclusion using wire cages, deer fencing, or burlap wraps installed in fall before deer pressure intensifies. Deer repellent sprays can be moderately effective when applied consistently and reapplied after rain, but no spray provides complete protection under heavy pressure. In areas with truly severe deer pressure, consider whether a deer-resistant evergreen alternative such as juniper, spruce, or falsecypress might be a more practical choice for the long term.

Winter care

Emerald Green arborvitae is cold-hardy through zone 3 and handles low temperatures well, but it can suffer two types of winter damage worth understanding and preventing. The first is desiccation or winter burn, which occurs when foliage loses moisture on warm, sunny, or windy winter days while frozen soil prevents root uptake. This shows up as browning foliage, typically on the south- or west-facing sides of the plant. A thorough late-fall watering before the ground freezes, combined with a good mulch layer, goes a long way toward prevention. Anti-desiccant sprays applied in late fall can also reduce moisture loss through the foliage during winter. The second concern is snow and ice damage. Heavy snow accumulation can cause the narrow columnar form to splay open or individual branches to break. You can gently brush accumulated snow off plants after a storm using an upward sweeping motion rather than shaking, which can cause more breakage. Wrapping plants loosely with burlap in areas with consistently heavy snow loads can prevent splaying while still allowing air circulation.

Pests and diseases

Emerald Green arborvitae is generally healthy when properly sited and maintained, but it’s susceptible to a few specific problems worth watching for. Bagworms are one of the most damaging pests, producing spindle-shaped bags made of foliage and silk that are easiest to spot and remove by hand in fall and winter when plants are bare. Left unmanaged, large bagworm populations can cause significant defoliation. Spider mites can be a problem during hot, dry weather, causing a stippled, dull, or bronze appearance on the foliage; a strong jet of water or treatment with insecticidal soap or horticultural oil can manage them effectively. Tip blight, caused by the fungus Kabatina thujae, can cause browning and dieback of shoot tips, particularly in wet springs; improving air circulation and avoiding overhead watering help prevent it. Root rot from Phytophthora can occur in poorly drained or consistently wet soils. Cypress tip moth larvae tunnel into shoot tips and cause tip dieback that’s sometimes confused with disease; removing and disposing of affected tips breaks the pest’s life cycle.

Landscape design

Emerald Green arborvitae’s narrow, upright form makes it one of the most space-efficient evergreens for creating privacy, screening, and structure in the residential landscape. Planted in a row 3 to 4 feet apart, it forms a dense, uniform privacy screen or living fence that provides year-round coverage without the horizontal spread of broader evergreens. Along a property line, fence, driveway, or the back of a border, it creates a strong vertical backdrop that frames the landscape and blocks unwanted views. As a foundation plant flanking an entryway or doorway, a pair of Emerald Green arborvitaes provides classic, symmetrical formality that suits both traditional and contemporary architecture. In a mixed evergreen border, its columnar form contrasts effectively with mounding or spreading companions like boxwood, ornamental grasses, and broadleaf evergreens. In containers at a formal entrance or on a patio, it provides year-round structure and a polished, intentional appearance. It also works beautifully as a specimen accent plant at a focal point in the landscape, where its clean, vertical silhouette draws the eye without overwhelming surrounding plantings.

Frequently asked questions

How far apart should I plant Emerald Green arborvitae for a privacy screen? For a solid privacy screen, plant them 3 to 4 feet apart on center. They’ll fill in within a few years to create a dense, uniform hedge. If you’re willing to wait a bit longer for full coverage or want a slightly airier screen, spacing them 4 to 5 feet apart also works well and gives each plant more room to develop naturally.

Why is my Emerald Green arborvitae turning brown? Browning has several possible causes. Winter desiccation is the most common, producing brown foliage typically on exposed sides of the plant in late winter or early spring. Drought stress during summer causes browning throughout the plant. Bagworms and spider mites can cause localized browning, and root rot from poorly drained soil causes browning that progresses from the bottom up. Identifying which part of the plant is browning and when it occurred helps narrow down the cause.

Does Emerald Green arborvitae stay green in winter? Yes, and this is one of its most valuable traits compared to other arborvitae cultivars. The ‘Smaragd’ cultivar maintains its rich emerald-green color through winter without the yellowish or bronze tint that affects many other arborvitae selections, making it one of the best choices for year-round color in cold climates.

How tall will Emerald Green arborvitae get? At maturity, expect 10 to 15 feet tall and 3 to 4 feet wide. Because it grows slowly to moderately, it takes many years to reach its full height, making it an excellent choice for spaces where a large, fast-growing tree would eventually become a problem.

Can Emerald Green arborvitae be grown in containers? Yes, it does well in large containers and is a popular choice for formal entryways and patio planters. Use a large, well-draining container and a high-quality potting mix. Container plants are more vulnerable to both drought stress and winter freeze-thaw damage than in-ground plants. In cold climates, move containers to a sheltered but cold location for winter or insulate the pot to protect the roots.

What can I plant instead of arborvitae in a deer-heavy area? If deer pressure in your area makes arborvitae impractical, consider juniper cultivars (Juniperus species), which are strongly deer resistant and provide similar evergreen screening. Blue spruce (Picea pungens), Norway spruce (Picea abies), and falsecypress (Chamaecyparis species) are also more deer resistant options that provide screening and evergreen structure.

Will Emerald Green arborvitae grow back after deer damage? It depends on the extent of the damage. If deer have browsed the tips of branches but left green foliage intact further back on the stems, the plant will typically recover over one to two growing seasons as new growth fills in. If deer have stripped branches back to bare wood, recovery is unlikely in those areas since arborvitae doesn’t regenerate from leafless wood. Severely damaged plants may need to be replaced.

Can I plant Emerald Green arborvitae near a fence or wall? Yes, its narrow form makes it well suited for tight spaces against fences and walls. Make sure it receives adequate sunlight on all sides if possible, since it will grow sparsely on the shaded side if light is very limited. Also ensure there’s enough space for the 3- to 4-foot mature width without the plant being compressed against the structure, which can trap moisture and reduce air circulation.