By April Sorrow
University of Georgia

For some gardeners, fall seems like a time of rest. A University of Georgia expert says fall is actually time to prepare your landscape for the winter.

In the fall, test soil for nutrients, apply fertilizer, prune flowering plants, replenish mulch and plant new trees and shrubs, said Bob Westerfield, a UGA Cooperative Extension horticulturist.

“One thing to do this fall is soil testing,” he said. “Amending your soil is one of the easiest ways to avoid plant stress or prevent future disease problems.”

A routine soil test takes two days to process and costs $6. To take a soil sample, use a clean plastic bucket and a spade. Collect samples four- to six-inches deep from four or five places in your landscape. Blend the samples in the bucket. Take this sample to your local UGA Extension office. There, you will get a soil sample bag and instructions for submitting the sample.

Determining the pH level of your soil will show if soil amendments are necessary. If needed, add lime in the fall. It takes three months to neutralize the soil, Westerfield said.

Fertilize in August

Annual flowering plants or blooming perennials, like roses, should receive their last fertilizer application in August.

“Hold off on any further fertilizer applications to flowering shrubs and summer annuals,” Westerfield said. “And resist the temptation to prune any woody shrubs during fall months. Doing so could cause a late flush that could easily suffer cold damage later on.”

Fall is the time to prune annual flowering plants and perennials like iris’ and day lilies. Cut back the foliage after stalks have browned out and withered over. Iris’ can be moved in August, too, shortly after the leaves brown.

Transition flower beds

Transition flower beds to display continuous fall color. Pull petunias and marigolds and plant cool-season annuals like pansies, snap dragons, mums or ornamental cabbages, he said. Choose colors that complement each other. A solid bed of white pansies in front of dark green hollies, for example.

Fall is also a good time to replenish mulch. Three- to four-inches of organic mulch, like straw or wood chips, should be added to beds. Mulch insulates roots and helps retain soil moisture. This protects the plant from cooler winter temperatures and Georgia’s dry climate.

Add new plants

If you are planning to add new plants to your landscape, fall is the perfect time.

“Cool temperatures are easier on newly installed plants,” Westerfield said. “It gives the plant time to root out, prior to the hot temperatures of spring.”

Westerfield reminds home landscapers to know the mature size of the plants they install. Select plants that fit the site you have chosen and won’t outgrow it. And be sure to follow proper planting procedures.

“Don't place shrubs in a straight row but in clusters,” he said. “Stagger them when laying them out. Try to cascade plants so the larger shrubs are in the back and place the smaller plants toward the front.”

When determining where to plant your shrubs, remember the rule of three; always plant in groups of odd numbers: three, five, seven, etc.

Keep an eye on irrigation, too. Even though fall temperatures are cooler, plants may still need additional water from irrigation.

“The moisture will help prevent plants from suffering cold damage when temperatures plummet,” Westerfield said.