To properly manage plants during a drought, soil maintenance is key

With the lack of rain, I am getting a lot of requests for information on how to help plants survive the drought.

//

The best way to make a plant drought-tolerant is to plant it properly. It doesn't matter whether you are planting shrubs, trees or grass, how you prepare the soil will determine how well the plant does.

Before you start working the land, you need to know the pH of the soil and what nutrients are available. It is easier to change the chemical makeup of the soil before the plants go in the ground than after they are planted. The best way to determine it is through a test of a soil sample, which will tell you if you need to add lime and how much fertilizer you need.

The next step is to till the soil. Plants that are drought-tolerant need the best rooting zone possible. This is accomplished by tilling the bed or turf area. Till the soil as deep as you can. The general guideline is 3 inches minimum, but the deeper the better.

Tilling the whole bed softens the soil so roots fill the bed area. The more roots, the better the plant handles drought. To prepare the soil like this takes more time, but you will have healthier plants. This guideline also applies to turf.

To better help rooting, amend the soil with compost, peat moss, topsoil or very fine ground pine bark. These products will help keep the soil from compacting, improve rooting, hold nutrients and water, and provide microorganisms to help the plant.

Adding sand to clay soil is not recommended. Sand doesn't hold nutrients or moisture. Also, when you add sand to a clay soil and the soil dries out, you have a brick. The sand can make the clay harder than it is normally.

Apply these soil amendments 2 to 3 inches deep across the area. This could be a flower bed, shrub bed or the area where you are going to plant grass. Then incorporate the amendment by tilling it in the soil.

Mulch will help plants conserve moisture when the temperature gets hot. The mulch is a barrier that slows down the evaporation of water from the soil. A 3- to 4-inch layer of mulch should be used around shrubs, flowers and trees. The mulch needs to extend to the end of the limbs on trees. In the flower and shrub beds, the mulch will help keep the soil loose and pliable.

Proper irrigation is the area where most mistakes are made. The biggest problem is not using enough water. Research has shown that most plants do best when they receive an inch of water a week. This water needs to be applied at one time unless you are on very sandy soils. Then, the water needs to be split into two applications.

I saw some research this week that showed a correlation between the frequency of watering and the amount of root mass that the turfgrass had. The grass that received water every day had a smaller root system than grass that received water every five days. In fact, the longer the grass went between irrigations, the larger the root systems. The roots had to look for water, so they produced a larger root system.

Plants with larger root systems are better able to withstand drought than plants with small root systems. If you are watering your grass three times a week for 20 to 30 minutes each time, your root system is going to be smaller than if you water deeply once a week.

When I talk about deep watering, I mean applying an inch of water. Also, you don't need to water unless your grass tells you it needs water. The sign of a grass needing water is when the grass turns a blue-gray color.

The last practice that you can do to help plants endure a drought is to give them plenty of potassium. This is the last number on a fertilizer bag. The plants don't need the nitrogen, but potassium helps with drought resistance and winter hardiness.

Plants can survive a drought if we treat them right.

Columbia County Extension Agent Charles Phillips can be reached at (706) 868-3413 or by e-mail at charlesp@uga.edu. The extension Web address is www.ugaextension.com/columbia.