Green Giant arborvitae is a fast-growing hybrid evergreen created by crossing Western redcedar with Japanese arborvitae. It holds dense, glossy green foliage through winter without the yellowing or browning that plagues many evergreens, and it grows in a narrow pyramid shape that reaches 40 to 60 feet tall. Homeowners plant it for privacy screens, windbreaks, and property-line hedging, and the steps used to plant an arborvitae hedge apply whether you set out two trees or fifty.
The appeal is speed and low fuss. Under good conditions the tree puts on 3 to 5 feet of growth per year, tolerates a wide range of soils, and handles both heat and cold once established. It also transplants well, which is rare among large evergreens. Its shaggy dark brown bark and small glossy leaves give it texture up close, and brushing the foliage releases a pleasant scent. For a screen that works within a few seasons instead of a decade, few evergreens match it.
Green Giant Arborvitae Care
Green Giant is one of the easiest conifers to grow, but it still has preferences. Plant it in full sun to part shade, give it well-drained soil, and water deeply during establishment. It adapts to clay, sand, and loam, and it performs across a wide hardiness range. When a hedge outgrows its spot or a tree fails, know how to remove arborvitaes safely and efficiently so the rest of the planting stays undisturbed.
Light, Soil, and Water
Full sun produces the densest growth. In heavy shade the canopy thins and the lower branches drop their foliage. Any well-drained soil works, though trees in wet, compacted ground grow slowly and become prone to root rot. Water new trees twice a week for the first season, then once a week through the second summer. Established trees need water only during extended drought.
Temperature and Hardiness
Green Giant thrives in USDA zones 5 through 8, with reports of success in zone 4 with protection and in warmer zone 9 locations. It handles winter ice and snow better than many arborvitaes because the branches are flexible and the upright form sheds snow. In hot inland zones, afternoon shade and a thick mulch keep the root zone cool.
Fertilizer Needs
Most soils supply enough nutrients. If growth is slow or foliage looks pale, apply a balanced slow-release fertilizer in early spring at the rate on the label. Skip late-summer feeding, which pushes tender growth that winter can damage. Newly planted trees drop a few inner needles in their first season; that is transplant stress, not disease, and the canopy refills by the second summer.
| Attribute | Green Giant arborvitae |
|---|---|
| Botanical name | Thuja standishii x plicata ‘Green Giant’ |
| Family | Cupressaceae |
| Mature height | 40 to 60 feet |
| Mature width | 12 to 18 feet |
| Growth rate | 3 to 5 feet per year |
| Sun | Full sun to part shade |
| Hardiness zones | 5 to 8 (USDA) |
| Soil | Well-drained, adaptable |
Pruning and Maintenance
Green Giant needs little pruning. Its natural pyramid shape stays tidy on its own, and the lower branches remain full as long as the canopy gets sun. Prune in late winter or early spring before new growth, and never cut into the brown interior of a branch, because arborvitae does not regrow from bare wood. If foliage starts to discolor, the causes and fixes covered in guides on arborvitae turning brown trace back to watering, winter burn, or pests in most cases.
When and How to Prune
- Wait until late winter or early spring.
- Remove dead or damaged branches at the trunk.
- Shape the tips by cutting back into green growth only.
- Thin crowded interior branches to improve airflow.
Shearing Hedges
For a formal hedge, shear lightly once a year after the spring flush. Keep the base slightly wider than the top so sunlight reaches the lower branches. Heavy shearing into old wood leaves bare patches that never fill back in, so stop at the green. Winter burn shows up in late winter as brown tips on the windward side; a burlap screen or anti-desiccant spray protects young trees in exposed sites, and damaged tips can be clipped off in spring once new growth begins.
Common Pests and Diseases
Green Giant resists many of the problems that affect other arborvitaes, but it is not immune. Bagworms spin cocoons in the foliage and defoliate branches if left unchecked. Spider mites cause fine stippling and bronzing during hot, dry spells. Root rot and canker diseases appear when soil stays wet. When a planting becomes too crowded or a tree declines past recovery, removal is sometimes the cleanest option, and knowing how to remove overgrown arborvitaes from your landscape keeps the job safe near houses and power lines.
Pest Control Steps
- Bagworms: pick off and destroy the bags in fall or winter, and spray Bacillus thuringiensis on young larvae in early summer.
- Spider mites: hose the foliage down during dry spells, and apply horticultural oil if infestations persist.
- Deer and rodents: fence young trees in winter and use repellents where deer browse heavily.
Disease Prevention
Prevention starts with drainage. Plant on raised beds or gentle slopes in heavy soil, and keep mulch a few inches away from the trunk. Water at the base rather than overhead to keep foliage dry, and space trees so air moves through the canopy. Root rot is the hardest problem to reverse: yellowing from the inside out, a thinning canopy, and a sour smell at the base all point to wet soil. Improve drainage, reduce irrigation, and remove the tree if the root ball is mushy.
Planting and Spacing for Hedges and Screens
Spacing decides whether your screen looks like a hedge or a row of trees. For a dense privacy hedge, plant 5 to 6 feet apart. For a windbreak or a looser screen where each tree keeps its own form, space them 8 to 10 feet apart. The fundamentals of how to select, plant and maintain arborvitaes apply to every variety, and getting the hole, watering, and mulch right at planting prevents years of struggle.
Planting Step by Step
- Dig a hole twice as wide as the root ball and no deeper.
- Set the tree so the root flare sits at ground level.
- Backfill with the original soil and skip amendments.
- Water deeply and mulch 2 to 3 inches deep, keeping mulch off the trunk.
- Stake only in windy sites, and remove the stakes after one year.
Spacing Quick Reference
| Purpose | Spacing | Result |
|---|---|---|
| Privacy hedge | 5 to 6 feet apart | Dense wall in three to five years |
| Windbreak | 8 to 10 feet apart | Individual trees, gaps close over time |
| Backdrop screen | 12 to 15 feet apart | Open tree form, room to grow |
Growing Green Giant in Containers and Small Yards
Green Giant’s mature size surprises owners who plant it in small lots. A 40- to 60-foot tree with a 12- to 18-foot spread is a major landscape feature, so measure the site before planting. In the early years it grows fast enough to screen a two-story house, and regular water is the key to that speed. As a renewable privacy screen, the tree also fits the wider shift toward sustainable landscaping, and the reasoning behind green building practices explains why fast-growing, low-input plantings reduce the long-term costs of a property.
Container Growing
Young trees grow well in large containers for several years. Use a pot at least 24 inches wide with drainage holes, and plan to repot or plant out within three to five years. Container trees need more frequent watering than in-ground trees, especially in summer. Check soil moisture weekly by pushing a finger 2 inches deep, and water when the top layer is dry; reduce frequency in winter when growth slows.
Planning for Mature Size
Check overhead utility lines, building eaves, and neighbor property lines before planting. The mature width of 12 to 18 feet means the tree needs clearance from structures. If the site is tight, choose a smaller arborvitae variety or a different screen species.
Frequently Asked Questions
How fast does Green Giant grow? Expect 3 to 5 feet per year once established, with the fastest growth in full sun and deep soil. How tall does it get? Mature trees reach 40 to 60 feet, though many homeowners keep hedges shorter with light pruning. Does it stay green in winter? Yes, the foliage holds its color through cold weather, which is why it replaced older arborvitae varieties in many hedges. For a hedge, spacing of 5 to 6 feet gives a solid screen, while wider spacing keeps individual tree forms.
Common Questions Answered
- How long until a hedge is private? About three to five years at 5- to 6-foot spacing.
- Can it grow in shade? It survives, but the canopy thins and the screen gets patchy.
- Is it toxic? Arborvitae foliage is not listed as toxic to people or pets, though deer browse it.
For more on connecting the yard’s plantings to the rest of the home, resources on building green link landscaping choices with energy use, water demand, and long-term property value, so the screen you plant today pays off beyond privacy.