The third Friday in January is Arbor Day in Louisiana – a day we set aside to appreciate trees and plant them. That’s Jan. 15 this year. If you are thinking about adding some trees to your landscape, planting should ideally be done now through early March when temperatures are cool and plants will have a chance to make root growth before the weather gets hot.
Trees are sold in one of two forms: container-grown or balled-and-burlapped.
Balled-and-burlapped trees are grown in the ground. When they reach the desired size, they are dug up with the roots covered by a soil ball, which is then tightly covered with burlap fastened with nails and either wrapped with twine or placed in a wire basket. When they are dug, the plants lose much or most of their root system and are prone to transplant shock, so they are best planted during the cooler months – October through early March.
Container-grown is the most common type of trees people buy. These plants have well-developed root systems and suffer less transplant shock when planted. For this reason, you may plant them almost year-round. Still, it is best to plant them from October to March during the milder weather we have then. Avoid planting in the stressful summer months.
No one tree is perfect for Louisiana. All trees have advantages and disadvantages, depending on the planting location and desired characteristics. Here are some points you need to consider:
– Select a tree that will mature at the appropriate size. I cannot stress this too much. Generally, small trees are those that grow from 15 to 25 feet tall; medium-sized trees grow from 30 to 55 feet tall, and large trees grow 60 feet tall or taller.
– Decide if you want a tree that retains its foliage year-round (evergreen) or loses its leaves in the winter (deciduous). Deciduous trees are particularly useful where you want shade in summer and sun in winter.
– Choose trees that are well adapted to Louisiana growing conditions, including typical temperatures and rainfall.
– Check the location of overhead power lines, and if you must plant under them, use small low-growing trees. Also consider underground water lines and septic tanks as well as walks, drives and other paved surfaces that may be damaged by the roots of large trees. Locate large trees at least 15 feet away from your house and paved surfaces.
When planting a tree, dig the hole at least twice the diameter of the root ball and no deeper than the height of the root ball. Remove a container-grown tree from its container, and place the tree gently onto the firm, undisturbed soil in the bottom of the hole. A root ball tightly packed with thick encircling roots indicates a root-bound condition. Try to unwrap or open up the root ball to encourage the roots to spread into the surrounding soil.
Set balled-and-burlapped trees in the hole with the burlap in place. Once the tree is in the hole, remove any nylon twine or wire basket that may have been used, and fold down the burlap from the top of the root ball.
The top of the root ball should be level with or slightly above the surrounding soil. It is critical that you do not plant the tree too deep.
Thoroughly pulverize the soil that was removed from the hole and use this soil, without any additions, to backfill around the tree. Research shows that blending amendments such as peat moss or compost into the soil used to fill the hole slows establishment. As a tree grows, its roots will grow out well beyond the reach of its branches. Because the roots will spend most of the tree’s life growing in native soil outside of the planting hole, they might as well get used to it from the beginning.
Add soil around the tree until the hole is half full, then firm the soil to eliminate air pockets, but do not pack it tightly. Finish filling the hole, firm again and then water the tree thoroughly to settle it in.
Adding fertilizer to the planting hole is not recommended, although it is all right to use some slow-release fertilizer in the upper few inches, if you like. Using a root stimulator solution is optional.
Stake the tree properly if it is tall enough to be unstable; otherwise, it’s not necessary. Generally leave the support in place no more than 9-12 months.
Keep the area 2 feet out from the trunk free from weeds and grass. This encourages the tree to grow faster by eliminating competition from grass roots and also prevents lawn mowers and string trimmers from damaging the bark at the base of the tree.
Water a newly planted tree whenever the weather is dry, particularly during the hot summer months. This is the single most important thing you can do to ensure its survival. To properly water a tree its first year, turn a hose on trickle and lay the end on top of the ground within 6 inches of the trunk. Let the water trickle for about 30 minutes. This should be done twice a week during hot, dry weather.
Dan Gill is a horticulturist with the LSU AgCenter. He can be reached at DGill@agcenter.lsu.edu.