The fall season is a great time to plant trees, and shrubs as well. During the spring, soils are cold and may be so wet that low oxygen levels inhibit root growth. The warm and moist soils normally associated with fall encourage root growth. Fall root growth means the tree or shrub becomes established months before a spring-planted tree and is better able to withstand summer stresses. Moreover, the best time to plant is in early September to late October. This is early enough that roots can begin to develop and become established before the ground freezes.
Fall-planted trees and shrubs need some special care. Remember that roots are actively growing even though the part of the plant above ground is dormant. Make sure the soil stays moist, but not soggy. This may require having to water them not only in the fall but also during the winter months, especially if the winter is dry and/or unusually mild. Mulch can be helpful because it minimizes moisture loss and slows the cooling of the soil so root growth continues that much more.
Note: there are certain trees that are an exception, as they do not produce significant root growth during the fall and are better planted in the spring. These include beech, birch, redbud, magnolia, tulip poplar, willow oak, scarlet oak, black oak, willows, and dogwood.
In either case, fall or summer, here are some hints you can remember when planting containerized trees and shrubs:
1) Dig the hole no deeper than the container bottom to the root flare or crown of the plant; on trees the flare needs to be slightly above the soil grade when done.
2) Dig the hole two to three times the diameter of the root ball or container, and the bottom of the hole needs to be undisturbed (not loosened).
3) When placing the plant into the hole, disturb the root ball as little as possible. Lift potted plants by the container, not by the trunk, stems or branches. Be sure to not allow the root system to dry out before or during planting.
4) Tip the container on its side and slide the plant from the container. Place the plant in the hole by lifting the root mass. If the roots are tightly matted, use a knife to score the root mass in several places and gently loosen the root ball.
5) Add backfill soil to the planting hole until it comes about halfway up the root ball. At this point the soil can be lightly packed by hand or foot, or by placing the hose in the hole and letting water run until the back filling is complete.
6) Construct a 3-4-inch high ridge of soil around the outer edge of the planting hole. This berm will create a basin to hold irrigation water, concentrating it over the roots.
Next week: Part II of this article, discussing how to transplant a shrub or tree from one location in your yard to another.
Rip Winkel is the Horticulture agent in the Cottonwood District (Barton and Ellis Counties) for K-State Research and Extension. You can contact him by e-mail at firstname.lastname@example.org or calling either 785-682-9430, or 620-793-1910.