There are many reasons to plant trees in your landscape. They provide shade, reducing air conditioning costs when planted on the southwest side of the house. Trees provide food to caterpillars, which then provide protein for hungry bird nestlings. In addition, studies have shown that being around trees is soothing to people, reducing stress. While fall is the best time to plant a tree, we often think about planting trees in the spring. March and April are good months to plant, so the tree can recover from transplant shock before the hot, dry summer weather arrives.
What to consider when shopping for a tree? If the spot where you wish to plant the tree is shaded, you will want to plant a tree that tolerates shade, such as serviceberry (Amelanchier spp) or a fringe tree (Chionantus virginicus). If the area is poorly drained, plant a species that can tolerate wet roots, such as river birch (Betula nigra).
Select a tree that will fit without requiring major pruning—topping a tree is not recommended! Do not plant trees that grow tall under a power line or trees that grow wide close to your house. For help in selecting a tree species, search online for “trees for Georgia UGA” to find the University of Georgia publications on recommended trees.
We think that roots grow down, but mostly they grow outward in the top 18 inches of soil. We once believed that tree roots spread out to the “drip line,” the outer edge of the tree’s canopy. We now know that tree roots will spread up to 3 times further out than the mature tree is wide. Consider root spread to avoid damage to pavement, especially if planting a very shallow-rooted tree such as maple or southern magnolia.
Select a healthy tree. Avoid trees that have obvious injuries to the trunk or are diseased. Also, reject plants with roots that are wrapped around the trunk. If feasible, pull the tree out of the pot and make sure that the roots are healthy and not badly circling, as these will eventually gird and kill the tree. Smaller trees, 3 to 7-gallon size, tolerate transplanting better and seem to catch up with the size of larger specimens in just 2 or 3 years. Smaller specimens also save money.
Dig the hole no deeper than the root ball. The flare where the trunk enters the soil should show above ground after planting. Remove fabric and wires from the roots of balled and burlap plants. Some fabrics will not rot, and the fabric and wires can harm roots. Make the hole 2 to 3 times as wide as the root ball and scarify the sides of the hole. Yes, this is hard work, but it pays off. Digging a wide hole breaks up the hard clay so the roots can expand easily. Since the tree roots will be competing for water and nutrients, getting rid of nearby grass will help the tree establish. Also, mulching a wide area will keep mowers and weed whackers from damaging the tree.
A major misconception is that you should mix in soil amendments before refilling the hole. Research has shown that the tree will do better if you just put back the well-loosened existing soil. You can put a couple of inches of compost on the top of the planting area.
Watering is vital. During the planting, once about half the soil is returned to the hole, water the hole well. Return the remaining dirt and then thoroughly water the plant. Your new tree will need at least one inch of water each week during the first year, and even into the second year if the summer is especially dry. Water deeply and infrequently.
Avoid “mulch volcanoes,” this is where mulch is piled up against the trunk. Mulch should be only about 3 inches deep and should be kept at least 2 inches from the trunk to protect it from fungi. Do not stake the tree unless necessary to keep it upright. Use nylon webbing to connect the trunk to the stake. Remove all staking after the first year. Do not prune the tree when planting except to remove dead, broken or diseased branches.
Give your tree the proper planting and care, and you will be rewarded amply.