Getting giant green arborvitae spacing right from day one prevents the heartbreaking task of digging up mature trees that have grown into each other. The exact spacing for your giant green arborvitae depends entirely on whether you want a dense privacy screen or a natural, open look.
Most homeowners plant these fast-growing evergreens too close together. They see small nursery pots and forget that a giant green arborvitae can reach 30 to 40 feet tall and spread 10 to 12 feet wide at maturity. Let’s fix that before you put a single shovel in the ground.
Giant Green Arborvitae Spacing
Giant green arborvitae spacing is not a one-size-fits-all number. The distance between each tree changes based on your goal, your soil quality, and how patient you are. If you want a solid privacy fence in three years, you will plant closer. If you want healthy, well-formed trees that live for decades, you need more room.
Here is the short answer: For a dense privacy screen, space your trees 5 to 6 feet apart. For a natural, uncrowded look, space them 8 to 10 feet apart. For a windbreak or sound barrier, 6 to 8 feet works well. These numbers assume you are planting in a single row.
Do not plant them closer than 4 feet apart. At that distance, the branches will interlock, but the root systems will compete for water and nutrients. The lower branches will die off, and you will end up with bare trunks and a thin canopy at the top.
Why Spacing Matters More Than You Think
When you plant giant green arborvitae too close together, the trees do not just touch. They rub against each other in the wind. This rubbing creates wounds on the bark. Those wounds become entry points for pests and diseases.
Overcrowded trees also block sunlight from reaching their own lower branches. Arborvitae do not regrow needles on bare wood. Once the lower branches die from shade, they stay dead. You cannot fix this later by pruning or fertilizing.
Another hidden problem is airflow. Tightly packed trees trap humidity. That trapped moisture creates the perfect environment for fungal diseases like Kabatina tip blight and Phyllosticta needle blight. Proper spacing keeps air moving through the foliage, which keeps the needles dry and healthy.
How To Measure Spacing Correctly
Measuring spacing is not about the distance between the trunks. It is about the distance between the outer edges of the mature canopies. When you read that a giant green arborvitae spreads 10 feet wide, that means the branches extend 5 feet out from the trunk on each side.
Follow these steps to mark your planting holes:
- Decide on your spacing distance (5, 6, 8, or 10 feet based on your goal).
- Run a string line along the area where you want the center of your trees to sit.
- Use a tape measure to mark each planting spot along the string.
- Place a landscape flag or a small stake at each marked spot.
- Stand back and look at the flags from different angles. Visualize the mature width of each tree.
- Adjust the flags if any tree will overlap its neighbor by more than one-third of its width.
If you are planting a double row for a thicker screen, stagger the trees. Place the second row 6 to 8 feet behind the first row. Offset the trees in the second row so they sit in the gaps between the trees in the front row. This zigzag pattern gives you a denser barrier without crowding any single tree.
Spacing For A Privacy Screen
Most people buy giant green arborvitae for privacy. You want to block the neighbors view of your backyard, pool, or patio. For this purpose, you are willing to sacrifice a little tree health for quick coverage.
A 5-foot spacing is the sweet spot for privacy. At this distance, the branches will start to touch within 2 to 3 years after planting. By year 5, you will have a solid green wall. The trees will be a bit crowded, but they will survive if you water them deeply during dry spells.
Do not go closer than 5 feet. I have seen homeowners plant at 3 feet apart because they wanted instant privacy. Ten years later, every single tree had dead lower branches and a thin, leggy top. They had to remove every other tree, which left gaps in their screen anyway.
If you want privacy faster without ruining the trees, buy larger specimens. A 6-foot tall tree in a 15-gallon pot will give you a screen much sooner than a 2-foot tall seedling. The extra cost is worth it compared to the cost of replacing crowded trees later.
Spacing For A Natural Look
If you are not building a privacy screen, give your giant green arborvitae room to grow naturally. These trees are beautiful as standalone specimens or as a loose grouping. Their natural shape is a narrow, pyramidal form with dense, dark green foliage.
For a natural look, space your trees 8 to 10 feet apart. At this distance, the trees will not touch at maturity. Each tree will keep its lower branches and its full, conical shape. You will see a bit of trunk at the base, but the canopy will be full from top to bottom.
This wider spacing also makes maintenance easier. You can walk between the trees to prune, inspect for pests, and water. You do not need a ladder to reach the interior branches because you can access them from the sides.
Natural spacing is also better if you live in an area with heavy snow or ice. Trees with room to sway in the wind shed snow better than trees that are locked together. Crowded trees collect snow in the gaps between their canopies, and the weight can split the trunks.
Spacing For A Windbreak
Giant green arborvitae are excellent windbreaks. They are evergreen, so they block wind all year round. They also tolerate cold temperatures and drying winds better than many other evergreens.
For a windbreak, plant your trees 6 to 8 feet apart. This spacing is a compromise between the dense privacy screen and the natural look. The trees will grow together enough to deflect wind, but they will not be so crowded that they damage each other.
Windbreaks work best when they are at least two rows deep. Plant the first row at 6 feet spacing. Plant the second row 10 feet behind the first row, with the trees offset. This staggered double row will slow the wind much more effectively than a single row.
Keep in mind that a windbreak does not stop wind completely. It slows the wind and pushes it up and over your property. The effective protection zone is about 10 times the height of the trees. A 30-foot tall windbreak will protect about 300 feet downwind.
Spacing For A Hedge Or Border
Some people want a low hedge or a border along a property line. Giant green arborvitae are not ideal for this because they grow so tall. But if you are committed to using them, you need to plan for their height.
For a hedge that you will keep trimmed to a specific height, plant at 5 to 6 feet spacing. You will need to shear the tops and sides every year to keep them in bounds. This regular pruning is labor-intensive, but it produces a formal, manicured look.
If you do not want to prune, choose a different plant. A giant green arborvitae that is not pruned will reach 30 to 40 feet tall. That is too tall for most residential borders. It will also cast a large shadow over your yard and your neighbors yard.
If you insist on using them for a border, check your local zoning laws. Some municipalities have height restrictions for trees near property lines. You do not want to plant a tree that you will be forced to cut down later because it violates a local ordinance.
Spacing For Sloped Ground
Planting on a slope changes the spacing math. On a hillside, the trees are not on the same horizontal plane. The distance between them should be measured horizontally, not along the slope.
If you measure along the slope, you will plant your trees too close together. The horizontal distance will be less than you think. This mistake leads to overcrowding and all the problems that come with it.
To measure horizontal distance on a slope, use a builder’s level or a laser level. Have a helper hold a measuring tape at the base of the upper tree. You stand at the base of the lower tree and hold the tape level. Read the measurement where the tape crosses the vertical line from the upper tree.
If you are planting on a steep slope, consider terracing. Create a flat planting shelf for each tree. This prevents water from running off the slope before it can soak into the roots. It also makes the trees easier to water and maintain.
Spacing And Soil Quality
Your soil quality affects how close you can plant your giant green arborvitae. In rich, deep, well-draining soil, the roots can spread out and find plenty of nutrients. You can plant slightly closer because the roots will not compete as fiercely.
In poor, rocky, or compacted soil, the roots will struggle. They will stay close to the surface and compete for every drop of water. In this situation, you need to increase your spacing by at least 2 feet. Give the trees more room so their roots do not have to fight each other.
Before you plant, do a simple soil test. You can buy a home test kit at any garden center. Check the pH, nitrogen, phosphorus, and potassium levels. Giant green arborvitae prefer a slightly acidic soil with a pH between 6.0 and 7.0.
If your soil is poor, amend it before planting. Mix in 2 to 3 inches of compost or aged manure into the top 12 inches of soil. This improves drainage and adds nutrients. Do not put fertilizer in the planting hole. It can burn the young roots.
Spacing And Watering
Watering is the most critical factor in the first two years after planting. Giant green arborvitae have shallow root systems. They cannot reach deep water during a drought. You must water them regularly, especially during the first summer.
With proper spacing, you can water each tree individually. Use a soaker hose or a drip irrigation line that runs along the base of the trees. Water slowly and deeply so the moisture reaches the entire root ball.
If your trees are too close together, you cannot water them properly. The water will pool on the surface between the trees and run off. The roots in the center of the clump will stay dry, while the roots on the outside get too much water. This imbalance stresses the trees and makes them vulnerable to disease.
A good rule of thumb is to water deeply once a week during the first year. In hot, dry weather, water twice a week. In the second year, you can reduce watering to every other week. By the third year, the trees should be established and need water only during severe droughts.
Spacing And Fertilizing
Fertilizing is not a substitute for proper spacing. You cannot fix overcrowded trees by feeding them more. In fact, over-fertilizing crowded trees makes the problem worse. It stimulates rapid growth, which makes the branches grow into each other even faster.
If you have spaced your trees correctly, you do not need to fertilize them heavily. A slow-release fertilizer formulated for evergreens applied once in early spring is sufficient. Follow the label directions for the size of your tree.
Avoid high-nitrogen fertilizers. They produce lush, soft growth that is more susceptible to pests and diseases. They also encourage the tree to put all its energy into top growth, neglecting root development. This makes the tree unstable and prone to blowing over in the wind.
If your trees are showing signs of nutrient deficiency, such as yellowing needles or stunted growth, test your soil first. Do not guess. You might have a pH problem that is preventing the tree from absorbing nutrients, even if the nutrients are present in the soil.
Spacing And Pruning
Pruning cannot fix a spacing mistake. If you plant your trees too close together, you cannot prune them to stay small. Arborvitae do not respond well to hard pruning. If you cut back into the brown, dead wood, the tree will not regrow needles there.
You can lightly trim the tips of the branches to encourage bushier growth. This is called shearing. But you cannot remove large branches without creating permanent bare spots. The tree will look ugly and unhealthy.
The only real fix for overcrowded arborvitae is to remove some of the trees. This is a hard decision, but it is better to lose one tree than to lose all of them. If you planted at 3 feet spacing, remove every other tree. This will give the remaining trees 6 feet of space.
If you catch the problem early, you might be able to transplant the crowded trees. The best time to transplant is in early spring or late fall when the tree is dormant. Dig up as much of the root ball as you can, and replant immediately. Water deeply after transplanting.
Common Spacing Mistakes
Here are the most common mistakes people make when spacing giant green arborvitae. Avoid these and your trees will thrive.
- Planting too close to a fence or wall. The tree needs room for its roots and branches to spread. Plant at least 4 feet away from any solid structure.
- Planting under power lines. A giant green arborvitae will grow into the lines and cause a hazard. Check the mature height before you plant.
- Ignoring the mature width. People focus on the height and forget about the width. A 10-foot wide tree needs 5 feet of space on each side.
- Planting in a single row for a windbreak. A single row is not effective. You need at least two staggered rows.
- Not accounting for the shadow. A 40-foot tall tree casts a large shadow. Make sure it will not block sunlight from your garden or solar panels.
Spacing For Different Climates
Your local climate affects how close you can plant. In humid, wet climates, you need more space between trees. The extra airflow helps prevent fungal diseases. In dry, arid climates, you can plant slightly closer because the low humidity keeps the foliage dry.
In cold climates with heavy snow, give your trees more space. Crowded trees collect snow and ice in the gaps between their canopies. The weight can bend or break the branches. With more space, the snow slides off naturally.
In windy coastal areas, plant your trees closer together. The wind will dry out the foliage and stress the trees. A tighter grouping provides some mutual protection. Just be sure to water deeply, because the wind will also dry out the soil.
Spacing And Companion Plants
You can plant other things between your giant green arborvitae, but you need to be careful. The arborvitae roots are shallow and competitive. They will steal water and nutrients from smaller plants.
If you want to plant ground cover or flowers between your trees, wait until the arborvitae are established. This takes about two years. Then, plant shallow-rooted perennials that can tolerate some shade and dry soil.
Good companion plants include hostas, ferns, and bleeding hearts. These plants thrive in the shade of the arborvitae and do not compete aggressively for water. Avoid planting grass right up to the base of the trees. Grass roots will compete with the tree roots.
Mulch is your best friend. Apply a 2 to 3 inch layer of organic mulch, like wood chips or bark, around the base of each tree. Keep the mulch a few inches away from the trunk. The mulch retains moisture, suppresses weeds, and regulates soil temperature.
How To Correct Spacing Mistakes
If you have already planted your trees too close together, you have a few options. The best option is to transplant the crowded trees as soon as possible. The younger the tree, the better it will survive the move.
If the trees are too large to transplant, you will need to remove some of them. This is painful, but it is the only way to save the remaining trees. Remove the weakest or most diseased trees first. Leave the healthiest trees with the most space.
If you cannot bear to remove any trees, you can try to keep them pruned. But as I mentioned, this is not a good long-term solution. The trees will still compete for resources, and they will eventually decline.
Sometimes, you can train the trees to grow away from each other. Use stakes and ties to gently bend the branches outward. This can create a little more space between the canopies. But this is a temporary fix, not a permanent solution.
Final Thoughts On Spacing
Getting the spacing right from the start saves you time, money, and heartache. Measure twice, dig once. Look at the mature width of the tree, not the size of the pot. Think about your long-term goals for your landscape.
If you are unsure, err on the side of more space. You can always plant a few extra trees in the gaps if you want a denser screen. But you cannot easily remove a tree that is too close to its neighbor without creating a permanent gap.
Take the time to plan your layout on paper before you start digging. Mark the spots with flags