How to Plant Evergreen Trees | Roots First, Then Growth

Getting the planting depth right is the single biggest factor in whether an evergreen thrives or slowly declines. A tree set too deep suffocates its roots; one set too shallow dries out. The good news is that the process itself is straightforward: pick the right spot, dig wide not deep, water thoroughly, and mulch correctly. This guide walks through each step so your tree establishes strong roots in its first season.

When Should You Plant Evergreens?

Early spring and early fall are the two windows that give evergreen roots time to establish before stress arrives. The New York Botanical Garden recommends planting between March 1 and April 15, or from mid-August through October 1. They specifically advise against late-fall planting because trees won’t harden off before frost and winter winds hit.

Cool weather is the goal. Roots grow whenever soil temperatures stay above roughly 40°F, even when the tree looks dormant above ground. Planting in early fall lets roots settle in before the ground freezes, and the tree is ready to push new growth in spring. If you plant in summer heat or deep winter, the tree faces double stress: transplant shock plus weather it can’t handle yet.

Choosing the Right Spot and Digging the Hole

Colorado State University Extension advises checking four things before you dig: soil drainage, sunlight, space at mature size, and clearance from driveways, sidewalks, entryways, and overhead utility lines. Most evergreens prefer full sun, though some tolerate partial shade — check your specific variety’s needs.

When you’re ready to dig, the hole shape matters more than most people expect. Multiple sources recommend digging the hole 1.5 to 3 times as wide as the root ball, but no deeper than the root ball itself. The Tree Center puts it simply: “Dig a hole the depth of the pot.” Wide holes let roots spread horizontally into loosened soil; deep holes cause the tree to settle and sink below grade, which is a leading cause of decline.

Before placing the tree, water the root ball or container so the soil holds together. Then set the tree in the hole so the top of the root ball sits level with or slightly above the surrounding ground — never below it. If you’re unsure about your soil’s drainage, dig a test hole, fill it with water, and see if it drains within a few hours.

Backfilling, Watering, and Mulching the Right Way

Once the tree is positioned, backfill with the native soil you removed. Don’t add compost, fertilizer, or soil amendments at planting time — MyPerfectPlants and conifer planting guides both stress this. Amended soil encourages roots to stay in the planting hole instead of spreading into the surrounding ground, which weakens the tree long-term.

Before backfilling, check the root ball. If roots are circling the sides or bottom, loosen them with your fingers or cut them — Fleet Farm recommends untangling or cutting spiral roots so they grow outward instead of strangling the tree over time. Gently work the soil around the roots, water thoroughly to remove air pockets, and finish filling.

Mulch is worth doing but easy to get wrong. Colorado State University Extension says all evergreens benefit from mulch, and Fleet Farm recommends 3–4 inches deep spread over the root zone. The critical rule: keep mulch away from the trunk. Piling mulch against the bark traps moisture and invites rot and pests. Leave a few inches of bare soil around the trunk, and don’t use plastic sheeting underneath — it blocks water and air from reaching the roots.

Watering Schedule for the First Year

The Tree Center recommends watering well at planting time, then once a week for the first season. That’s the baseline, but adjust for your climate.

Colorado State University Extension adds an important caveat: most evergreens need supplemental water during dry, warm, or windy periods from November through March. Evergreen foliage keeps losing moisture all winter, even when the ground is frozen and roots can’t replace it. If you’re in a dry or windy winter region, water your evergreen on mild days when the soil isn’t frozen.

Deep, infrequent watering beats frequent shallow watering. A slow trickle at the base for 30–60 minutes reaches deeper roots than a quick splash. Grand Valley State University recommends weekly watering or more during hot, dry weather, continuing through the first year until the ground freezes.

Common Mistakes That Kill Newly Planted Evergreens

Knowing what not to do is half the battle. The most consistently identified problems across extension services and planting guides are:

• Planting too deep. The root ball should sit at or slightly above grade — never buried.
• Skipping root loosening. Circling roots eventually girdle the tree and cut off its own circulation.
• Planting in late fall in regions with harsh winters. The tree can’t harden off in time.
• Adding fertilizer or amendments at planting. This burns young roots and discourages outward growth.
• Letting mulch touch the trunk. It traps moisture and invites disease.

If you follow the basics — right timing, wide shallow hole, proper depth, consistent water, and clean mulch — your evergreen has everything it needs to establish. If you’re still deciding which variety fits your yard, take a look at our roundup of the best evergreen trees for home landscapes to compare mature sizes, sun needs, and growth rates before you dig.