Tree Planting Guidelines
By Betsy Washington
Following a few simple planting guidelines can insure that your new shade trees get off to a healthy start and grow vigorously. First, think carefully about where to plant your new tree and be sure to consider the mature size of your tree. All of these trees will mature into grand specimens and can ultimately reach 50 – 70’ or more in height and spread. Be sure there is plenty of room for the tree to grow; look up and make sure there are no overhead utility lines nor buildings or structures that may inhibit the tree’s growth in future years. Trees are best planted about 15 or 20’ away from buildings or houses. Likewise, make sure there are no underground obstructions or utilities nearby. Once you have decided where to plant your tree, keep a few simple rules in mind. The two most common causes of loss of new plants are: 1) water stress from allowing the plant to dry out either before it is planted or during the first year or two after planting; and, 2) planting too deeply. If you cannot plant your tree immediately, store it in a cool, shady spot and be sure to keep it well watered. Most of the roots of trees are located in the top foot or so of soil and extend out into the soil 2 to 3 times past the dripline at the outer edge of the tree’s canopy.
Delfino and his crew will be preparing the planting hole and planting your new tree for you, but I am including some general rules for planting trees that may be useful to you in the future.
Preparing and Planting a Tree:
- Dig a wide, shallow hole; the wider the better. The hole should never be deeper than the depth of the rootball or container that the tree was growing in and the rootball should sit on undisturbed soil to prevent settling. Use your shovel as a guide to determine how deep to dig the hole. Make sure the hole is at least 2 – 3 times the diameter of the rootball – the wider, the better!
- If possible consider designing an entire bed or border around your new tree and adding complementary groundcovers or shrubs when you plant. Lawn grass inhibits the full development of tree roots, so a mulched border of groundcovers and shrubs is most beneficial to the future health of your tree and will give your landscape a “finished, professional look’.
- If your soil tends to be poorly drained, dig the hole only 2/3’s as deep as the rootball, so that 1/3 of the rootball sits above the surface of the soil. Then taper the backfilled soil up to the edge of the top of the rootball, being careful not to cover it with soil.
- If you have sandy or loamy soil, you may add amendments such as compost or leaf mold to the backfill soil, to loosen and enrich it. A couple of tablespoons of micorrhizal innoculant will add beneficial fungi to your soil and will help the roots of your new tree extract more nutrients and water from the soil. It will also encourage healthy populations of microorganisms that will loosen, and improve your soil’s health over time. Micorrhizae also help trees endure stress, drought, and resist disease and insect pests.
- Once you have prepared your hole or bed, lift your new tree by the rootball or container, not the trunk. Use the trunk only to steady the tree as you move it. If your plant is in a container, cut the container away or tap it sharply and carefully remove your plant. Inspect the rootball to make sure the roots do not encircle or girdle the rootball.
- If your plant is pot-bound, tease the encircling roots apart with your fingers so that they are loose and face outwards, or cut the rootball with a sharp knife or shovel making 4 or 5 one inch deep vertical slits or grooves around the rootball and then gently tease the roots apart.
- Place the plant in the hole and be sure the flare of the trunk is just above the soil surface.
- If you have a balled and burlapped plant, carefully place it in the hole, then carefully cut away and remove as much of the burlap and rope as possible. At a minimum, be sure to cut away all the wrappings from the top and sides of the rootball so that they do not inhibit growth of the fine root hairs as they spread laterally. Never leave a wire mesh basket on a tree – this will eventually girdle the roots. To avoid compromising the rootball, cut the bottom rungs of the wire basket before the tree is placed in the hole, then after situating it in the hole, carefully cut the rest of the basket away from the rootball.
- Carefully backfill the hole with soil, firmly but gently tamping the soil down around the roots. If the tree is planted on a slope, it may be helpful to create a small “lip” or mound of soil around the lower edge of the planting hole, to help hold rain water in the root zone until it has time to soak in.
Tips for Caring for Your New Tree:
- Be sure to water your new tree thoroughly right after it is planted. This is easily done by placing your hose next to the trunk of the new tree and let it gently drip and soak into the soil for a half hour or until the soil is soaked to the depth of the rootball.
- You do not need to fertilize your tree at planting time since this can burn tender new roots, and cause excessive top growth at the expense of root growth. Wait until the following year to add a slow release fertilizer or mulch annually with compost which will provide all the nutrients your tree needs.
- Tree wrap and staking are no longer recommended, and may actually encourage disease and retard growth.
- Place 2 – 3” of mulch around your tree leaving a couple of inches immediately adjacent to the trunk free of mulch. This is plenty of mulch – do not be tempted to create a “volcano” of mulch around your tree as this encourages fungal diseases and rot and causes water to run off of the mulch away from the root zone.
- Be sure to water your new tree thoroughly for the first year or two, especially in times of drought – about 1” of water is needed per week. This fall, it may be helpful to let a hose drip slowly over the rootball for an hour or so twice a week if we don’t have rain. You can feel the soil around the rootball to see if it is dry. Next year, be sure to continue watering at least once a week, when we have not had rain. After the first year or two your new tree should have developed a strong root system and will be able to withstand moderate droughts. As with all trees, they are a life-long investment and it makes sense, to soak their roots once every couple of weeks during dry periods.
- Your tree should not need pruning. Remove only damaged or broken branches the first year.