How to Plant a Tree

An image of planting a tree

Fall is a great time to replace the trees lost or to add even more beauty, shade, privacy and wind protection to your landscape.

By Tim Gamma

This article was first published in The Gateway Gardener October 2011 issue.

Fall is a great time to replace the trees lost or to add even more beauty, shade, privacy and wind protection to your landscape. Tree planting is a lifetime investment. How well your tree grows depends on the type of tree and location you select for planting, practices followed during planting, and follow up care the tree receives after planting. These will significantly affect its chance of survival and vitality.

As an arborist for over 25 years, I have observed countless examples of trees planted in the wrong place, poor site conditions, and most prominently planted too deep. Closely behind are trees planted and over mulched with nylon twine and burlap intact that leads to stunted and girdled trees.

If the tree you are planting is balled and burlapped, or bare rooted, it is important to understand that the tree’s root system has been reduced by 90-95% of its original size during transplanting. As a result of the trauma caused by the digging process, trees will commonly exhibit “transplant shock.” Proper site preparation before and during planting, coupled with good follow-up care will reduce the amount of time the plant experiences transplant shock and will allow the tree to quickly establish in its new location.

The following steps will help you avoid the above pitfalls and plant a tree properly.

An illustration of proper planting holes for tree plantingDig a shallow, broad planting hole. Make the hole wide, as much as three times the diameter of the root ball, but only as deep as deep as the root ball (see diagram). It is important to make the hole wide because the tree roots on the newly established tree must push through surrounding soil to establish. Breaking up the soil in a large area around the tree provides the newly emerging roots room to expand into loose soil to hasten establishment.

Identify the trunk flare. The trunk flare is where the roots spread at the base of the An illustration of a tree-planting hole and identification of the root flare.tree. This point should be partially visible after the tree has been planted. If the trunk flare is not partially visible, you may have to remove some soil from the top of the root ball. Find it so you can determine how deep the hole needs to be for proper planting.

Place the tree at the proper height. Before placing the tree in the hole, check to see that the hole has been dug to the proper depth, and no more. The majority of the roots on the newly planted tree will develop in the top 12 inches of soil. If the tree is planted too deep, new roots will have difficulty developing due to lack of oxygen. It is better to plant the tree a little high, 2-3 inches above the base of the trunk flare, than to plant it at or below the original growing level. This will allow for some settling. To avoid damage when setting the tree in the hole, always lift the tree by the root ball, and never by the trunk

Straighten the tree in the hole. Before you begin backfilling have someone view the tree from several directions to confirm the tree is straight. Once you begin backfilling it is difficult to reposition.

Back fill the hole. Fill the hole about 1/3 full gently but firmly pack the soil around the base of the root ball. Then, if the tree is balled and burlapped, cut and remove the nylon string and burlap from around the trunk and top 1/3 of the root ball. The top of the wire basket should be cut if present. Be careful not to damage the trunk roots in the process. Fill the remainder of the hole taking care to firmly pack soil to eliminate air pockets that may cause roots to dry out. To avoid this problem water slowly to settle the soil. Continue this process until the hole is filled and the tree is firmly planted.

Stake the tree, if necessary. If the tree is grown and dug properly at the nursery staking for support is not necessary in most home landscape situations. Studies have shown that trees will establish more quickly and develop stronger trunk and root systems if they are not staked at the time of planting. However, protective staking may be required on sites where vandalism or windy conditions are concerns.

Mulch the base of the tree. Organic mulch applied to the area at the base of the tree acts as a blanket to hold moisture, protect against harsh soil temperatures, both hot and cold, and reduces competition from grass and weeds. A two or four inch layer is ideal. When placing mulch, care should be taken so the actual trunk of the tree is not covered. This may cause decay of the living bark at the base of the tree. (DO NOT BUILD MULCH VOLCANOES!)

Follow-up care. Keep the soil most but not soaked, overwatering will cause leaves to turn yellow or fall off. Water trees at least once a week, barring rain, and more frequently during hot weather. When the soil is dry below the surface of the mulch, it is time to water. Container grown trees are even more susceptible to drying out and may require more frequent watering. Other follow-up care may include minor pruning of branches damaged during the planting process. Prune sparingly immediately after planting, and wait to begin necessary corrective pruning until after a full season of growth in the new location.

Trees are a lasting addition to any landscape. Routine care will ensure survival and aesthetic beauty. When questions arise about the care of trees, be sure to contact your local member of the St. Louis Arborist Association, ISA Certified Arborist or a reputable nursery center for assistance.

Tim Gamma is co-owner of Gamma Tree Experts. He is a board certified master arborist (#MW-0117B) with a BS in Horticulture, and is immediate past president of the International Society of Arboriculture. Gamma Tree Experts was founded in 1954 and with locations in University City and Chesterfield, and serves municipalities, country clubs, institutions and thousands of homeowners each year. To learn more, key