A Guide to Planting Trees

Spring and fall are the optimum seasons for planting trees. And although all newly planted trees experience some transplant stress, proper planting techniques can minimize the stress and get your trees off to a healthy, vigorous start.

Select a Site

Consider the size of your tree, you soil and how much sun it needs. Trees are an investment and they take years to grow to maturity so select your site carefully. Avoid planting them under or near overhead utility wires, and before you start digging, call your utility company to find out about hidden underground wires or pipes.

Special site considerations: Seedlings up to 12 inches tall can be spaced close together for protection (1 foot apart) for the first two years and then relocated to a permanent location when dormant. Evergreen seedlings, except junipers and cedars, should be planted in partial shade for the first few years to more closely mimic forest conditions.

Determine the Proper Depth

A tree planted too deeply will not thrive (it may not survive). The tree's root collar (the bulge right above the root system) should be just above the top of the soil. Many trees are planted too deep at the nursery so you may need to remove soil down to where the first large side roots occur.

Prepare the Site

Prepare the site by digging a large saucer-shaped hole that is 2 to 3 times larger than the root ball. Remove any sod or grass and till or break up the soil to a depth of 10 to 12 inches, but no deeper than you plan to plant the tree.

Dig a second hold in the center of the saucer that is 1 foot larger in diameter than the root ball and as deep as the root collar. Maintain undisturbed soil beneath the root ball to prevent the tree from settling. It is better to have the tree too high than too deep.

Set In the Tree & Refill the Hole

Place the tree carefully in the center of the hole and back fill the hole only when the tree is straight and correctly positioned. As much as possible, use the soil that was removed from the hole as backfill. As back fill is added, lightly push the soil around the roots and add water to the soil to eliminate air pockets (do not pack the soil after you water). Refill the hole with soil to the height just below the root collar. Again, be sure not to plant it too deep.

Mulch & Water Thoroughly

Apply a mulch of wood chips around the tree to a depth of 4 inches on top of the planting circle, keeping it at least 4 inches away from the trunk to prevent mold or fungus from growing. Water is very important to young trees, especially for the first year. A slow, root saturating one-hour trickle once a week is a good rule of thumb. This will provide the new roots sufficient moisture without drowning them. If it rains or is very dry, be sure to adjust your watering schedule accordingly.

Fertilizing

Fertilizers need to be applied carefully and in small quantities-especially in the first year. Trees arriving in containers are likely to have fertilizer in their root balls. Small amounts of compost or well rotted manure can be mixed in with the backfill during planting, but otherwise the trees can be left to settle in without fertilizer during the first year. Once on a regular schedule, trees should not be fertilized after October 1st.

Pruning

During the first 1 to 2 years limit your pruning to shortening the more vigorous branches for a neat appearance and remove any damaged, rubbing or crossing branches. As the plants mature, begin annual maintenance pruning.

Staking

Large, bareroot trees should can be staked with a single stake 3/4 the height of the tree. Set the stake in the hole 2 to 4 inches out from the center of the hole at the time of planting. Fill in the hole-tree, stake and all-and secure the stake to the tree using wire or rope. Cover the wire or rope with rubber at point of contact so you don't damage the bark. Container, ball or burlapped trees can be supported using parallel stakes set at least 18 inches out from either side of the hole. Remove stakes after the first year to avoid girdling the tree and hindering growth.

Planting Balled & Burlapped Trees

Balled and burlapped trees have the root ball held together by burlap that is usually encased in a wire basket or secured with twine. These trees are generally larger than trees in containers and can weigh several hundred pounds. In general, balled and burlapped trees are planted the same as bare-root trees, with a few special considerations.

In order to keep the root ball intact, do not removed the wire basket or burlap until the tree is positioned in the hole.

Before planting, carefully loosen the top of the burlap and probe the base near the trunk with a wire or remove some soil to determine where the root collar is located (right above where the large roots begin). Dig the planting hole to a depth to just cover these roots'no deeper.

Carefully place the tree in the hole and cut away as much of the wire basket as you can without disturbing the soil ball and cut and remove all twine and rope from around the ball. Remove any nails or staples holding the burlap together and gently fold the burlap back and cut away the exposed burlap without damaging root ball. Leave the remaining burlap and/or wire under the root ball. Roots grow out, not down.

Trees in Containers

Container trees come usually come in paper or plastic containers or wooden bushel baskets.

It isn't safe to assume that container trees have been planted in their containers at the correct depth. Remove the soil down to the root collar where the first large side roots begin just to determine the right depth for planting.

Try to determine if the tree roots hold the soil together in the pot or if the soil is loose. If the soil is packed or the pot is root bound, carefully remove the tree from the pot. You may have to lay the tree on its side and press the pot to free it from the soil ball.

If the tree's roots are wound tightly inside the pot (it seems they usually are), make a vertical slice up each quarter of the root ball (1 - 1 1/2" deep) and cut an X across the bottom of the soil ball. Continue planting in a normal manner.

If the tree is too large or the root ball is loose, place the tree and pot in the planting hole and adjust for final position. Next, carefully cut around the base of the pot. Then make a slice up one side of the pot. Gently back fill and then remove the sides of the pot. If you need to, you can leave the bottom of the pot in the hole. Roots grow out, not down.