How to Plant an Arborvitae Row

An arborvitae row can turn an exposed backyard into a leafy retreat, soften an unattractive fence, block winter wind, and politely suggest that the neighbors enjoy their own patio furniture. Better yet, arborvitae stays green throughout the year, so your privacy screen does not disappear the moment the leaves begin falling.

However, creating a healthy evergreen hedge involves more than buying a parade of shrubs and dropping them into equally spaced holes. The variety must fit the site, the spacing must account for mature width, and every plant must be installed at the correct depth. A row planted too tightly may become crowded and diseased, while one planted too deeply can decline before it ever becomes a useful screen.

This guide explains how to plant an arborvitae row correctly, from measuring the site and choosing a cultivar to watering, mulching, pruning, and preventing common problems.

Why Arborvitae Works Well as a Privacy Screen

Arborvitae belongs to the genus Thuja, a group of evergreen conifers known for flattened sprays of scale-like foliage. Depending on the species and cultivar, arborvitae may grow as a compact column, a broad pyramid, or a very large tree.

Homeowners commonly plant arborvitae rows because the plants offer:

• Year-round color and privacy
• Dense foliage that helps soften noise and wind
• Narrow cultivars suitable for smaller residential yards
• Relatively low maintenance after establishment
• A naturally formal appearance without constant trimming

The important phrase is “after establishment.” Newly planted arborvitae requires consistent moisture and careful monitoring. These plants are not demanding divas, but they do notice when nobody waters them for three weeks in July.

Step 1: Choose the Right Arborvitae Variety

Do not choose a cultivar based only on the height printed on a garden-center sign. Mature width, growth rate, climate tolerance, soil conditions, and available space are equally important.

Emerald Green Arborvitae

Emerald Green, also sold as ‘Smaragd,’ is a popular choice for residential privacy rows. It typically develops a narrow, upright form and matures at approximately 10 to 15 feet tall and 3 to 4 feet wide. Its moderate growth rate makes it easier to manage around patios, property lines, and smaller suburban lots.

For a dense screen, Emerald Green arborvitae is often planted about 3 to 4 feet apart on center. Giving each plant approximately 4 feet generally provides better air movement and reduces long-term crowding.

Green Giant Arborvitae

Green Giant is considerably larger and faster growing. Under favorable conditions, it can grow several feet per year and ultimately reach 40 to 60 feet tall with a spread of approximately 12 to 18 feet.

This cultivar is best for large properties where a tall screen, windbreak, or visual buffer is needed. Although young Green Giants may look harmless enough to fit beside a walkway, mature specimens are not polite little columns. They are trees, and they eventually behave like trees.

For a privacy row, Green Giant arborvitae is commonly spaced around 5 to 8 feet apart. Wider spacing allows each tree to develop a healthier root system and more natural shape.

Other Useful Cultivars

North Pole, Holmstrup, Techny, DeGroot’s Spire, and American Pillar are additional options. Their mature dimensions differ significantly, so check the cultivar label and confirm expected size with a trusted local nursery or Cooperative Extension office.

These spacing figures are practical starting points rather than universal laws. Local climate, soil, cultivar characteristics, and the desired density of the row should guide the final decision.

Step 2: Select a Suitable Planting Location

Provide Enough Sunlight

Arborvitae generally performs best in full sun, meaning approximately six or more hours of direct light per day. Many cultivars tolerate partial shade, especially afternoon shade in hot regions, but excessive shade can produce thin, open foliage.

Observe the site at several times during the day. A location that appears sunny at noon may be shaded by a house, fence, or mature tree during much of the morning and afternoon.

Check Drainage

Moist soil is welcome; permanently waterlogged soil is not. Poor drainage limits oxygen around the roots and can encourage root rot. Avoid low areas where water remains after rain.

To perform a basic drainage test, dig a hole about 12 inches deep, fill it with water, let it drain, and fill it again. If water remains for an unusually long period, correct the drainage or select another planting location. Do not assume that adding gravel to the bottom of each hole will solve a serious site-wide drainage problem.

Avoid Salt Exposure

Many arborvitae cultivars are sensitive to salt. Keep the row away from locations exposed to heavy road-salt spray, deicing runoff, or highly saline irrigation water. Plants beside a winter roadway may develop brown foliage even when watering and planting depth are otherwise correct.

Allow Space From Structures

Measure from the center of the future trunk, not from the edge of the nursery container. Leave adequate clearance from buildings, fences, sidewalks, overhead wires, septic systems, and neighboring property.

Before digging, contact the appropriate local utility-marking service. A privacy hedge is useful. A privacy hedge planted directly through a utility line is less useful.

Step 3: Determine How Many Arborvitae You Need

Measure the total length of the proposed row and divide it by the intended on-center spacing.

For example, suppose you want to plant a 48-foot Emerald Green arborvitae screen using 4-foot spacing:

48 feet ÷ 4 feet = 12 planting spaces

Depending on whether you need plants precisely at both ends, the final number may require a small adjustment. Lay out the entire row before buying or digging so you can verify the appearance and avoid squeezing an extra tree into the final six inches.

Step 4: Mark a Straight and Even Row

Place stakes at the two ends of the planting area and stretch a mason’s line between them. Use a tape measure to mark each planting center with landscape paint, small flags, or additional stakes.

Measure every position from the same starting point. Measuring from one plant to the next can compound small errors, producing a row that slowly drifts sideways like a shopping cart with one stubborn wheel.

If the property line is not perfectly straight or the landscape has curves, follow the intended visual line rather than forcing the hedge into an awkward geometric arrangement.

Step 5: Prepare the Arborvitae for Planting

Water container-grown plants thoroughly before installation. A hydrated root ball is easier to remove from the container and less likely to crumble.

Inspect each plant for:

• Broken, dead, or damaged branches
• Dry or unusually light root balls
• Circling roots around the container wall
• Trunks buried beneath excess nursery soil
• Bagworms, mites, scale insects, or suspicious discoloration

Remove the container and examine the roots. If thick roots are circling tightly around the root ball, loosen, straighten, or carefully cut them. A thin outer layer may also be shaved from a severely pot-bound root ball to encourage roots to grow into the surrounding soil.

For balled-and-burlapped plants, identify the root flare before setting the tree at its final depth. Once the root ball is stable in the hole, remove all twine from the trunk and cut away as much burlap and wire as practical, particularly from the upper portion of the root ball.

Step 6: Dig Wide, Shallow Planting Holes

Dig each hole approximately two to three times wider than the root ball but no deeper than the root system. Wide holes loosen surrounding soil and make it easier for new roots to expand horizontally.

The bottom of the hole should remain firm and undisturbed. Loose soil underneath the plant may settle later, causing the arborvitae to sink below grade.

Find the Root Flare

The root flare is the area where the trunk widens and transitions into major roots. It should remain visible at or slightly above the surrounding soil level after planting.

Nursery soil may cover the flare, so do not automatically treat the top of the root ball as the correct planting depth. Carefully remove excess soil until the uppermost structural roots become visible.

Place a shovel handle across the hole to compare the root flare with the surrounding grade. In poorly drained or heavy clay soil, setting the root flare an inch or two above grade can help account for settling and improve oxygen availability.

Step 7: Position and Backfill Each Plant

Place the arborvitae in the center of the hole and rotate it until the fullest side faces the main viewing area. Check the plant from several directions to make sure it stands vertically.

Backfill with the native soil removed from the hole. In most ordinary landscapes, replacing all the soil with compost, peat moss, or commercial planting mix is unnecessary. A sharply amended planting hole can behave like a container, encouraging roots to remain inside instead of entering the native soil.

Add soil in stages and water during backfilling to settle it around the roots. Gently press the soil with your hands, but do not stomp it into concrete. Roots need both moisture and oxygen.

Step 8: Water Thoroughly

Immediately after planting, soak the entire root ball and surrounding soil. Slow watering helps remove air pockets and ensures that the interior of the root ball becomes moist.

For the first growing season, inspect the soil regularly rather than following an inflexible calendar. Push a finger, trowel, or soil probe several inches into the root zone. Water when the soil is beginning to dry, but do not keep it continuously saturated.

A practical starting schedule may include deep watering two or three times per week during warm, dry weather, with adjustments for rainfall, temperature, plant size, and soil type. Sandy soil dries quickly, while clay may remain wet much longer.

Drip tubing or a soaker hose can water an arborvitae row efficiently. Check the system occasionally by digging into the soil. A hose may run for an hour while delivering surprisingly little wateror quietly creating a swamp around one unlucky tree.

Step 9: Apply Mulch Correctly

Spread approximately 2 to 3 inches of organic mulch over the root zone. Wood chips, shredded bark, and pine bark help conserve moisture, moderate soil temperature, and reduce competition from grass and weeds.

Keep mulch several inches away from the trunk. Do not build mulch volcanoes around the stems. Mulch piled against bark traps moisture, hides the root flare, and may contribute to decay, insects, and abnormal root growth.

For an entire arborvitae hedge, a continuous mulched bed is usually easier to maintain than individual circles surrounded by turf. Grass competes strongly with young roots and invites accidental damage from string trimmers.

Step 10: Care for the New Arborvitae Row

Water Through Dry Periods

Continue monitoring soil moisture for at least the first two growing seasons. Even established arborvitae benefits from deep watering during prolonged drought. Shallow, frequent sprinkling encourages roots to remain near the surface, where they are more vulnerable to heat and dryness.

Delay Fertilizer Unless Testing Shows a Need

Do not automatically fertilize newly planted arborvitae. Excess fertilizer does not correct drainage problems, poor spacing, root damage, or inadequate watering. A soil test can identify whether nutrients or pH adjustments are actually necessary.

Prune Lightly

At planting time, remove only broken, dead, or badly damaged branches. Arborvitae naturally develops an attractive shape and usually does not require aggressive pruning.

If shaping is needed, prune lightly before the spring growth flush. Avoid cutting deeply into brown, leafless interior wood because old arborvitae stems may not produce new foliage. Also avoid heavy late-summer or fall pruning, which can stimulate tender growth before winter.

Prepare for Winter

Water the row deeply before the ground freezes if autumn has been dry. Adequate soil moisture helps evergreens replace water lost through their foliage during winter.

In exposed locations, burlap screens can reduce drying wind without wrapping wet fabric tightly against the plants. Multi-stemmed arborvitae may also be loosely secured before heavy snow or freezing rain to reduce splitting.

Common Arborvitae Row Problems

One Plant Turns Brown

When a single plant declines while the rest remain healthy, inspect that tree individually. Common causes include a dry root ball, damaged roots, poor planting depth, localized drainage trouble, animal injury, or a blocked irrigation emitter.

The Entire Row Develops Brown Patches

Widespread browning may result from drought, winter burn, salt exposure, excessive watering, or unsuitable site conditions. Interior branchlets may also turn brown and drop naturally as they age, particularly in fall. Browning concentrated inside the plant is less alarming than progressive dieback at the outer tips.

Foliage Becomes Thin and Open

Insufficient sunlight and overcrowding are frequent causes. Dense spacing may create quick privacy, but it also reduces air circulation and light penetration as the plants mature.

Bagworms Appear

Bagworms produce spindle-shaped bags covered with foliage fragments. Small populations can be removed by hand when practical. Larger infestations should be identified and treated promptly because severe feeding can defoliate evergreen branches.

Deer Eat the Lower Foliage

Arborvitae is a favorite winter buffet in many deer-heavy areas. Fencing is generally more dependable than expecting a single repellent application to protect the row all season. Before purchasing dozens of plants, ask nearby gardeners how local deer treat arborvitae. Their answer may save you from installing an expensive salad bar.

Experience-Based Lessons From Planting Arborvitae Rows

The following practical observations reflect common outcomes seen in real residential landscapes. The first lesson is that smaller, healthy plants often establish more successfully than oversized specimens. A six-foot arborvitae creates immediate visual impact, but it also has a heavier root ball, greater water demand, and more transplant stress. A well-watered three- or four-foot plant may adapt quickly and begin vigorous growth while a larger neighbor spends two seasons looking offended by the move.

A second lesson is to inspect every root ball separately. Plants purchased together may not contain equal moisture. In one row, nine root balls may be damp while the tenth is nearly dry because water repeatedly flowed around its compacted growing medium. Surface irrigation can make the surrounding soil look wet even though the center remains dry. Directing water slowly onto each root ball during the first several months prevents the mysterious “one brown tree in the middle” problem.

Spacing regret also appears frequently. Young arborvitae looks narrow, and open space between plants can make a new hedge feel unfinished. This tempts homeowners to reduce spacing. The decision looks brilliant for several yearsuntil branches press together, lower foliage receives less light, and maintenance becomes difficult. Choosing the correct mature spacing requires patience, but temporary gaps are easier to tolerate than removing every other tree from an established hedge.

Another useful experience is to test irrigation output rather than trusting the label on a hose or emitter. Soil type, water pressure, line length, slope, and clogged openings all affect delivery. Place containers at several points along the row to compare output, then inspect the soil after watering. The goal is a deeply moistened root zone, not a decorative damp circle on top of the mulch. On sloping ground, short watering cycles with pauses between them can reduce runoff and improve absorption.

Finally, a straight row is not automatically a successful row. The best planting may shift slightly to avoid a wet pocket, provide clearance from a fence, or protect plants from road salt. A gentle curve can also look more natural than a rigid line. Good landscape planning balances appearance with long-term plant health. The arborvitae does not care whether the row is mathematically perfect; it cares about sun, oxygen, moisture, and enough room to grow.

Final Thoughts

To plant an arborvitae row successfully, start with a cultivar that fits the available space. Mark accurate on-center spacing, dig holes wider than the root balls, expose the root flares, and keep the plants at or slightly above the surrounding grade. Backfill with native soil, water deeply, and apply a flat layer of mulch without covering the trunks.

The first year demands the most attention, especially during hot or dry weather. Once established, a properly located arborvitae row can provide decades of greenery, privacy, and structure without requiring weekly negotiations with pruning shears.

Note: Plant performance varies by cultivar, climate, soil, and local pest pressure. This article synthesizes guidance from U.S. university extension programs, botanical institutions, and arboretums. Consult a local Cooperative Extension office for recommendations tailored to your region.