Fall is the ideal time to plant trees, shrubs, vines, groundcovers and herbaceous perennials.
Cool fall temperatures are less stressful to plants than the heat of late spring and summer because there is less water loss from the foliage through transpiration. For us in south Georgia, these temperatures exist throughout the winter months also.
Plants established during fall require less frequent irrigation and are less likely to die from heat-related stresses than those planted in spring and summer.
Another advantage of fall planting is that above-ground portions of the plant stop growing and go dormant, which lessens the demand on the roots for water. Roots, on the other hand, do not go dormant and continue to grow throughout the winter. So when spring arrives, a healthy, well-developed root system will be in place to absorb water and nutrients.
Ornamental plant physiology is different from that of turfgrass physiology. There is little to no activity of warm season grass roots in the winter. This is why planting warm season grass is better in May and June. With frequent irrigation, grass roots take to the soil and become established.
Does this mean we absolutely cannot plant any ornamental plant during the summer? No, it does not. In fact, many professional nursery operators plant ornamentals throughout the growing season. When an older plant has established roots in a pot, transplanting into the ground is less stressful. Professionals know each plant's stress levels and water requirements. The key to summer planting is plenty of water. Without an irrigation system, this can be very difficult.
Before planting ornamentals, check soil drainage by digging a hole approximately 15 inches deep by 15 inches in diameter and fill it with water. If water is left standing in the hole after one hour, the site may be poorly drained and need improvements. If you plant in undisturbed soil, research shows digging the hole at least two times wider than the width of the root ball provides a more favorable environment for root growth. "Never put a ten dollar tree in a two dollar hole."
Organic and inorganic amendments improve growing conditions also. Organic amendments originate from something once alive: composted yard waste, livestock manure, or peatmoss. Inorganic amendments are mined or man-made, such as vermiculite, perlite, and sand. Inorganic amendments improve the structure and drainage of the soil. Organic amendments also provide nutritional value.
Go ahead and water the plants before removing them from their containers. This is because it is difficult to re-wet a dry root ball once it is in the ground. Sometimes roots become pot-bound, which is when roots grow densely along the edge of the root ball. Do not be afraid to use a knife to open up the root mass before planting. This encourages new root growth and allows water to move inside the root ball.
If the plant root ball is wrapped in balled-and-burlap (B&B), cut the wire around the trunk and remove the burlap off the root ball so it does not impede root growth. For large trees with B&B, removing the top third of burlap is sufficient. It is OK to create a small 4-to 6-inch berm along the perimeter of the planting hole to funnel water to the roots. However, rake away the berm a month after planting so roots are not later eroded.
Hold the fertilizer until the plant is established. Granular fertilizers can dehydrate the roots of new plants. Because the plants are stressed from planting, waiting to fertilize with a sprinkle of 8-8-8 or 10-10-10 is best. Additionally, organic amendments provide nutrients at planting without injuring roots.
And I save the best for last. How deep do you plant? I answer calls on many dying plants that were planted too deep. They can actually be planted to shallow also. It is best to set the top of the root ball level with the soil surface. Planting too deep restricts oxygen movement to the roots in which they suffocate. On the other hand, planting too shallow may expose roots to the sun and wind, causing them to dry out and die.
This article was based off UGA Publication, "Make Every Drop Count: Proper Planting Results in Healthy, Water-Efficient Plants.”
For additional questions, contact Thomas County Extension office at 225-4130.