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When To Plant Thuja Green Giant (+ Planting & Care Guide)

When To Plant Thuja Green Giant (+ Planting & Care Guide)

The Thuja Green Giant is an excellent option for landscaping, suitable for properties of all sizes and layouts.

Whether you’re looking for the best and biggest evergreens or nice and neat hedgerows, Green Giants deserve a spot high on your list of potential trees to plant.

But, what is the best time of the year to put Green Giants into the ground?

When should you plant Thuja Green Giant? The most suitable time to plant Thuja Green Giants is in the spring. Planting at this time allows the trees to establish their roots and stabilize themselves before cold weather sets in. However, this hardy evergreen species may survive being planted almost any time that it isn’t freezing outside.

Below you’ll discover everything you need to know about when and how to plant Green Giants.

Thuja Green Giant Planting Guide

Planting Green Giants is less complicated than planting many other species because they are so hardy and adaptable. 

However, as with any species, there are several steps and considerations to take into account when planting Thuja that will practically guarantee success.

Best Time of Year To Plant Thuja Green Giant

The very best time of the year to plant this tree species is during the spring. Once the ground has thawed out after the winter, Thuja is ready for planting all the way up until the fall.

Of course, the sooner you plant them after the winter, the better their chances are of surviving their first winter in the ground.

That’s why spring is the most recommended time of the year for planting the species.

Thuja Green Giant Spacing

Depending on how you want your Thuja Green Giants to grow, the proper spacing ratio varies. 

For a hedgerow of Thuja, place each tree between 5 and 6 feet apart. The closer you plant them, the quicker they form into a solid hedge.

Once a hedgerow forms, you may shape it however you like.

For large individual Green Giants that may reach heights of over 50 feet, place the holes for the trees anywhere from 8 to 20 feet apart.

Keep in mind that full-size Thuja may grow up to 20 feet wide or more.

Lighting and Soil Amendments

The amount of light and the type of soil that Thuja Green Giant requires to grow and thrive is much less demanding than other species. 

As long as the trees get a few hours of sunlight per day, even if it is indirect, they will survive just fine. If they receive several hours of direct sunlight, they will grow even faster.

As far as the soil goes, Thuja Green Giants are just as lenient as they are with the amount and type of sunlight they receive.

Basically, Thuja will grow in just about any type of soil even though they may prefer an acidic growing medium.

If your soil is particularly poor, you can add finished compost to your fill dirt before filling in the hole. A mix of 50% compost and 50% native soil would be ideal.

The most important detail to mind when about your Green Giant’s soil is its level of moisture. The soil should be consistently and constantly moist but not soaking wet and waterlogged.

Digging the Hole and Planting

There is no one-size-fits-all measurement for digging the hole and planting Thuja.

Rather, because they come in many shapes and sizes, the general rule of thumb is to create a hole that is roughly twice as deep and wide as the container in which your Thuja has been growing.

Once the hole is prepared, add several inches of loose soil to the bottom. Place the tree into the hole, and make sure to spread the roots out in all directions.

Continue adding dirt after the roots are covered, layer by layer, packing the earth gently before adding each new layer.

Fill the hole in completely, and water to help the soil settle and eliminate air pockets. Mound dirt up 3 to 5 inches high around the tree’s trunk to complete the planting.


To help maintain the moisture level of the soil as well as to protect the roots from cold, disease, and pests, mulching your Thuja Green Giants after planting is highly advised.

To do so, simply spread any mulch of your choice up to 4 or 5 inches deep and up to two feet in diameter around the base of the tree.

Grass, wood chips, even acidic pine needles work for Thuja mulch.

Thuja Green Giant Care & Maintenance

A single, small, recently planted Thuja Green Giant tree.

Caring for Green Giants is even easier than planting them! 

They need very little attention from you, hardly any fertilizer (if any), and never REALLY need pruning unless you desire a certain shape or neatness to your trees/hedges.


Newly planted Thuja require watering every 48 to 72 hours or so, depending on the type of soil. It needs to be consistently wet near the roots but not soggy.

After trees are established, watering may be required as much as once per week or as little as once per month, depending on current weather conditions.


Green Giants are famous for growing in almost any condition, which means they don’t need fertilization.

If you wish to fertilize them, a slow-release general-purpose 10-10-10 formula, like this affordable, large bag, works just fine.


Surprise, surprise: Thuja doesn’t need pruning like many evergreens do. Hedges made of Thuja, however, benefit from a trimming session once every year or two.

If you want to give your Thuja unique shapes, pruning them is the magical ticket.

Related Questions:

Can You Plant Thuja in Winter?

Technically speaking, yes, you can plant Thuja in the winter, but is it a good idea? Probably not… unless you live in a place that doesn’t get down to freezing temps during the winter.

It is best practice to plant Thuja while there is enough time to establish new growth before the coldest parts of the year.

Do Thuja Green Giants Grow in Winter?

During the winter, Thuja goes into a dormant period just as must plants and trees do.

That’s why even though they stay “green” all year, they do turn slightly golden-brown or bronze during the coldest winter months. This is normal and no cause for concern.

A Final Word About Planting and Caring for Thuja Green Giant

Planting and caring for Thuja Green Giants, thankfully, isn’t nearly as complicated as dealing with other evergreen species.

These versatile trees do best when planted in the spring, but they can handle planting almost any time of the year.

Furthermore, they are among the easiest hedgerows and evergreen trees to care for, period.