Evergreen trees offer year-round color and structure in a landscape, but their long-term health depends entirely on proper planting techniques. Unlike deciduous trees, evergreens retain their foliage year-round and continue to lose moisture even in winter. This continuous need for water makes the successful establishment of the root system a particular challenge. Correct installation practices are important to minimize transplant shock and ensure the tree develops a robust root structure capable of supporting its decades of growth.
Selecting the Site and Preparing for Planting
The ideal time for planting evergreens is during the dormant or semi-dormant seasons of early spring or early fall. These periods feature cooler air temperatures and warmer soil, which reduces moisture stress on the foliage while encouraging new root growth. Planting four to six weeks before extreme conditions are expected allows the tree a sufficient establishment window.
A thorough site assessment must precede any digging to ensure the location meets the tree’s needs at maturity. Consider the ultimate height and width of the species to ensure it will not interfere with buildings, utility lines, or other structures. Analyzing the soil’s drainage is also important, as evergreens require well-drained conditions to prevent root rot.
To check drainage, dig a 12-inch deep hole and fill it with water; if the water remains after 24 hours, the site is unsuitable without significant modification. Before planting, container-grown trees require the identification of the root flare, the point where the trunk widens at the soil line. Remove excess soil from the top of the root ball to expose this flare, as it must sit at or slightly above the finished grade.
Bare-root stock should be soaked in water for one to two hours before planting to rehydrate the fine root hairs lost during transit. For all stock, inspect the root ball carefully and prune any circling or kinked roots. If left uncut, these roots can eventually girdle the trunk and restrict nutrient flow.
The Step-by-Step Installation Process
Begin by digging a planting hole that is shallow but wide, specifically two to three times the width of the root ball. The depth of the hole should be measured precisely so that the root flare rests at least level with, or preferably one to two inches above, the surrounding soil grade. Planting too deeply is a common error that suffocates the roots and leads to long-term decline.
Set the tree into the center of the hole, ensuring it is straight before proceeding with the backfilling process. For trees wrapped in burlap or wire baskets, remove all ropes and the top one-third of the wire basket once the tree is stabilized. Synthetic burlap must be completely removed to allow root expansion into the native soil.
Use only the native soil removed from the hole to backfill, as adding amendments like compost can create a textural difference that discourages roots from growing outward. Fill the hole halfway, then gently tamp the soil to remove large air pockets without compacting the soil excessively. After the first layer of backfill, water thoroughly to settle the soil and eliminate any remaining air pockets.
Finish filling the hole with the remaining native soil, ensuring no backfill covers the root ball itself. Create a temporary soil berm or dike around the perimeter of the planting hole, forming a shallow basin. This basin will capture and direct water inward, ensuring water soaks directly down to the new roots.
Immediate Aftercare for Establishment
The most important step immediately following installation is a deep saturation of the planting area. Fill the temporary watering basin with water and let it fully drain, then repeat this process two to three times. This initial deep watering helps settle the soil around the roots and is the foundation for establishment.
Maintaining consistent moisture without over-saturating the soil is important during the first year of establishment. New evergreens typically require deep watering two times per week during the growing season if there is no significant rainfall. The goal is to deliver enough water to penetrate the soil to a depth of six to twelve inches, encouraging the roots to grow downward.
Apply a two- to four-inch layer of organic mulch over the entire planting area to conserve soil moisture and regulate soil temperature. Keep the mulch several inches away from the trunk and the root flare to prevent moisture from collecting against the bark. This practice avoids the harmful “mulch volcano” effect.
Staking is generally unnecessary and can hinder the tree’s development, but it may be required for tall trees in extremely windy locations or areas with shallow soil. If staking is needed, use broad, flexible material and secure the ties loosely, allowing the trunk a small amount of movement to build strength. Remove stakes within one to two years to prevent the ties from girdling the trunk as the tree grows.