Published on 08/14/08

Plant now and save water

By April Sorrow
University of Georgia

Most Georgians are aware of the importance of conserving water, both inside and outside the home. In the landscape, a great way to save water is by planting during the cooler fall season, says a University of Georgia horticulturist.

Spring = short establishment time

Trees and shrubs planted in the spring often don't have time to get established before they’re exposed to the sizzling summer heat, said Gary Wade, a horticulturist with the UGA College of Agricultural and Environmental Sciences.

As temperatures rise, developing leaves, fruit and flowers demand more water and the root system may not be able to satisfy the demand, he said. If watering schedules are limited due to drought conditions, plants may die of thirst.

When a plant's top demands more supplies than the roots can provide, it starts abandoning branches or dropping leaves in a fight for survival.

Fall is less stressful, more successful

"Planting in the fall is much less stressful for the plant than springtime planting," Wade said.

Trees and shrubs grown in containers can be planted anytime, he said. But if you plant in the fall, as the weather cools down, the plant has a much better chance for survival.

"Roots don't go dormant," he said. "They keep growing all winter. Even though the tops of deciduous plants go dormant for the winter and the tops of evergreen plants slow down, roots continue to grow. Since the tops demand little from the roots, the plant’s energy can be funneled to the roots for growth and establishment."

Fall-planted ornamentals also have a supply of carbohydrates and other food substances stored in their roots from the previous growing season. This stored energy helps roots establish while the rest of the plant rests.

"When spring arrives, the plant will be able to pop with growth," Wade said.

Other advantages of fall planting are less water loss due to evaporation from the soil and from foliage as temperatures cool down. For these reasons, the plant requires less water while establishing.

Follow these tips

Planting in the fall is very similar to spring planting. "The only big difference is that you don't want to fertilize when you plant in the fall," he said. "Wait until next February." Wade offers some basic fall planting tips:

• Plant groupings of shrubs in beds thoroughly cultivated eight to 12 inches deep.

• For a single shrub, dig a planting hole at least twice as wide and as deep as the plant's root ball.

• Make sure the planting site drains well.

• When planting balled-and-burlapped plants, cut the cord or wire from around the stem and remove it. Then remove the top third or half of any burlap or fabric from around the root ball.

• Place the plant at the same depth it was grown in the nursery. Make sure the top of the root ball is level with the soil surface.

• Fill the hole with the soil you removed. Lightly pack it with your hands, water when it's half filled and again when completely filled to remove air pockets around the roots.

• Cover the planting surface with three to five inches of mulch, such as pine straw, pine bark or even fall leaves. This is always important, but even more critical during a drought. Mulch conserves water.

• Water. Plants need water anytime it's dry no matter which season. However, in the fall, they're much more forgiving if you're a day late watering them.

Use care around trees and shrubs

When adding new plants, minimize soil disturbance around existing trees and shrubs. When planting around established trees and shrubs, it’s best to plant in individual holes instead of cultivating an area and cutting roots of adjacent plants.

“Most roots are within the top 12 inches of soil and the roots of established trees and shrubs can extend two to three times farther than their canopy spread,” Wade said. “When you dig and cut roots, you’re affecting the plant’s ability to absorb water and nutrients.”

April R. Sorrow is a science writer with the University of Georgia Public Affairs Office.