!! Before you dig, check for underground utilities by calling the Oregon utility notification locate center hotline at 811 or 503-246-6699 (local) or 1-800-332-2344 (toll-free). If the planting soil does not need to be amended before the tree is planted, dig a hole approximately two times the width of the root ball.
Adding planting mixes: In most cases, soil does not need to be amended and the planting hole should be backfilled with the soil which was removed. Amendments should not be used unless the soil is very poorly drained or heavily urbanized. Consult your nursery specialist for information on how to amend soil. If soil amendments are needed, the planting hole should be dug three times wider than the width of the root ball.
Step 1: Dig a hole for the tree
The depth of the hole should not be deeper than the depth of the root ball. The tree's root flare should be visible once the planting hole is backfilled, but the roots should be covered with soil. Planting a tree too deep is a significant cause of tree failure in the urban area.
Step 2: Place the tree in the hole
If the tree is in a container, gently remove the container prior to lifting the tree into the planting hole. It is helpful to have 2-3 people lift the tree out of the container. Remember to lift the tree by the base of the trunk. If the roots are circling the inside of the container, gently but aggressively break up only the encircling roots to encourage normal growth and prevent tree girdling. Circling or girdling roots can inhibit establishment and may lead to premature tree death.
If the tree is balled and burlapped, remove as much wire, string, burlap, and plastic as possible. Be careful not to fracture the root ball. Once the outer materials are removed as much as possible with the root ball still intact, place the ball in the planting spot. You may have to cut some of the materials away at this point, leaving the bottom of the burlap. If necessary, remove excess topsoil in the ball in order to expose the root flare. Lift the tree into the planting hole by the root ball, not by the trunk.
Step 3: Fill the hole
Once the tree is in the ground, make sure the tree is straight and begin backfilling with soil. Break up dirt balls and water as you fill. Gently tamp the soil, but do not compact the soil too much! The tree needs soil with a good combination of air and dirt.
Step 4: Mulch
Mulching retains moisture for the tree, provides nutrients for the tree, removes competition from other plants, and prevents damage from lawn mowers and weed whackers. A good rule of thumb for applying mulch is the 3-3-3 rule: lay mulch down in a 3-inch thick layer, 3 inches away from the trunk of the tree, and in a 3-foot radius circle around the tree. Pile the mulch up around the edge of the circle to create a berm, directing water towards the tree. Keeping the mulch away from the trunk of the tree prevents trunk decay as well as the formation of surface roots.
Step 5: Stake the tree
Improper staking can prevent the tree from developing a strong, healthy trunk and supportive roots. Most trees do not need staking. However, staking can be a helpful visual protective barrier in high-traffic places such as school yards and street planting strips.
Place 2-4 stakes around the tree at the edge of the mulch pile. Make sure the stakes are pounded securely into the ground so they cannot be easily pulled out. Loosely tie the tree to the stakes with twine or another flexible material. The ties should be located no higher than 2/3 the height of the tree. The tree should be able to sway in the wind, which helps establish strong support roots and trunk. Check the twine periodically to make sure there is room for the tree to grow and the twine is not damaging the trunk. Remove the twine immediately if there are signs of damage on the trunk. Do not leave trees staked for more than one year or the tree may not develop its own proper support structure.