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The best time to plant green giants is in the early spring or early fall, as these seasons offer the mild temperatures and moist soil that Thuja Green Giants need to establish strong roots before extreme weather hits.
If you’ve been wondering when to plant green giants in your landscape, the answer depends on your local climate, but these two windows are almost always your safest bet for success.
Planting green giants in the spring gives them a full growing season to settle in before winter, while a fall planting lets them focus on root development without the stress of summer heat.
In this post, we’ll break down the best timing for planting green giants, the factors that influence when to plant, and the steps you should take to give your trees the best possible start.
Let’s dig into the details so you can confidently decide when to plant green giants in your yard.
When to Plant Green Giants for the Strongest Growth
The ideal time to plant green giants is when the soil is workable and the air temperatures are cool, which typically means early spring after the last frost or early fall about six weeks before the first hard freeze.
These periods are perfect because the trees are not actively pushing new foliage, and the cooler weather reduces the risk of transplant shock.
When you plant green giants during these mild windows, the roots can slowly acclimate to their new home while still having enough warmth to start growing.
This timing also allows the trees to establish a deep root system, which is critical for their long-term health and wind resistance.
The exact timing for when to plant green giants will shift depending on whether you’re in a northern, southern, or transitional climate zone.
Spring Planting: The Most Reliable Window
Spring is the most popular time to plant green giants because it gives the trees the entire growing season to get comfortable.
You should aim to plant green giants in the spring after the danger of frost has passed, usually between late March and early May in most regions.
The soil is naturally moist from winter rains and snowmelt, which helps the roots stay hydrated as they begin to expand.
Another reason spring is ideal for planting green giants is that the increasing daylight and warming soil temperatures signal the roots to grow actively.
This early root development translates into a robust tree that can handle the heat of summer and the cold of the following winter.
If you miss the early spring window, you can still plant green giants in late spring, but you’ll need to water more frequently to combat the rising temperatures.
Fall Planting: The Hidden Gem for Root Development
Fall is often overlooked, but it’s actually a fantastic time to plant green giants, especially in warmer climates where summers are brutal.
The best fall window for planting green giants is typically from late August through October, depending on your first frost date.
When you plant green giants in the fall, the air is cool, so the tree doesn’t lose much water through its leaves, while the soil is still warm enough to encourage root growth.
This combination means the tree spends all its energy on establishing new roots rather than supporting top growth.
By the time winter arrives, the roots are already anchored, which gives the tree a massive head start for the following spring.
Just make sure you plant green giants early enough in the fall so they have at least four to six weeks to establish before the ground freezes.
Factors That Affect When You Should Plant Green Giants
Beyond the seasons, several key factors will influence the precise timing for when to plant green giants in your specific situation.
Understanding these variables will help you avoid common mistakes and ensure your trees thrive.
Your Hardiness Zone
Your USDA hardiness zone plays a huge role in when to plant green giants because it determines your frost dates and temperature extremes.
In zones 3 through 5, where winters are harsh, spring planting is often the only safe option because fall-planted trees might not have enough time to root before deep freezes.
In zones 6 through 8, you have the flexibility to plant green giants in both spring and fall, with fall being slightly more forgiving for root growth.
In warmer zones 9 and 10, you can almost plant green giants year-round, but you should still avoid the peak of summer heat, so late fall and early spring remain the best bets.
Soil Temperature and Moisture Levels
Green giants prefer soil that is consistently moist but not waterlogged, and the soil temperature should be above 50°F for optimal root activity.
If you plant green giants when the soil is too cold, the roots will go dormant and won’t grow, leaving the tree vulnerable to drying out.
If the soil is too hot and dry, as it often is in midsummer, the roots will struggle to take up water, and the tree may suffer from heat stress.
You can test the soil temperature with a simple probe, and if it’s within that sweet spot, it’s a good time to plant green giants.
Bare-Root vs. Container-Grown Trees
The type of tree you purchase will also dictate when to plant green giants.
Bare-root green giants, which are sold without soil around their roots, must be planted in early spring before they break dormancy, as they cannot survive long out of the ground.
Container-grown green giants, which are the most common, can be planted a bit later because their root balls are intact and less prone to shock.
If you buy container trees, you have a wider window for when to plant green giants, but you’ll still want to avoid the extreme heat of mid-July and the frozen ground of deep winter.
How to Plant Green Giants for Maximum Success
Once you’ve determined the right time to plant green giants, the next step is to do the job correctly so your trees don’t just survive but truly flourish.
Choose the Right Location
Green giants need full sun to partial shade, so pick a spot that gets at least six hours of direct sunlight each day.
They also need well-draining soil, so avoid areas where water tends to pool after heavy rain.
Since green giants can grow up to 30 feet tall and 12 feet wide, make sure you give them plenty of space from structures, fences, and other trees.
A good rule of thumb is to plant them at least 4 to 5 feet apart if you want a dense privacy screen, or further apart if you want them to grow as standalone specimens.
Dig the Hole Properly
Dig a hole that is twice as wide as the root ball but no deeper than the root ball itself.
This is one of the most critical steps when you plant green giants because planting too deep can suffocate the roots and lead to rot.
Place the tree in the hole so that the top of the root ball is level with the surrounding soil.
Then, backfill the hole with the native soil you removed, gently tamping it down to remove air pockets.
Avoid adding compost or fertilizer at planting time, as this can actually burn the young roots.
Water Thoroughly and Mulch
After you plant green giants, give them a deep, slow watering to settle the soil and hydrate the roots.
Then, apply a 2-to-3-inch layer of organic mulch, like wood chips, around the base of the tree, being careful to keep the mulch a few inches away from the trunk.
Mulch helps retain soil moisture, regulates soil temperature, and suppresses weeds, all of which are essential for young green giants.
For the first few weeks after planting green giants, you’ll need to water them deeply once or twice a week, depending on rainfall, to keep the root zone consistently moist.
So, When Should You Plant Green Giants?
You should plant green giants in the early spring or early fall, as these seasons offer the perfect balance of cool air, warm soil, and adequate moisture.
If you’re in a colder climate, prioritize spring planting green giants to give them the longest possible establishment period before winter.
If you’re in a warmer climate, fall is an excellent choice for planting green giants because it allows the roots to grow steadily through the mild winter.
Remember to consider your hardiness zone, soil conditions, and the type of tree you’re buying to fine-tune your exact planting date.
The most important thing is to avoid extreme heat and extreme cold, as both will stress your trees and slow their growth.
By picking the right time to plant green giants and following the simple planting steps outlined here, you’ll be rewarded with fast-growing, lush, and resilient privacy trees that will enhance your landscape for decades.
So, get out there and get your green giants in the ground at the right time, and they’ll reward you with incredible vertical growth and dense foliage in no time.