Maddy: Liming and why it’s important

Published 5:17 pm Friday, November 10, 2017

One of the most frequently asked questions is why plants in the landscape are not growing well. The most frequent response is: When is the last time that you soil tested? Soil testing is a diagnostic tool that can solve a lot of headaches.

The most important information on the soil test recommendation is the pH level. The pH level indicates the acidity or alkalinity level of the soil. Most plants require for optimum growth a pH range between 6.0 and 6.5, slightly acidic. The pH scale ranges from 0 to 14 with 7 being neutral.

Why is this important? If the pH is below 6, nutrients such as nitrogen, phosphorus, potassium, sulfur, calcium and magnesium become unavailable. What this means is that you can apply all the fertilizer you want and if the pH is below 6, the plants will not be able to use it. Roots will just not grow well. The plants will therefore be deficient in these nutrients.

Soils in Georgia are naturally acidic. If you plan on growing azaleas, rhododendrons, blueberries or broom sedge a low pH would be alright. Since most garden plants and landscape plants require slightly acidic soil, liming becomes necessary. It can take up to a year for lime to react in the soil, so it’s essential that you do it as soon as you can.

Lime is ground up limestone rock. The two most common are Dolomitic limestone and Calcitic limestone (or High-Cal). Dolomitic contains both calcium carbonate and magnesium. If your soil lacks magnesium you can kill two birds with one stone by applying Dolomitic limestone. Calcitic is almost 100% calcium carbonate.

Limestone is sold by particle size. The smaller the size particle, the quicker the product will neutralize the soil where the roots are pulling the nutrients. The powder sized particles are more difficult to spread but react quicker. The sand size particles can be spread with most garden spreaders fairly easily.

When is the best time to soil test and lime? Now is the time to soil test and apply lime for spring and summer plant growth. It takes up to six months for lime to work in the soil. So, the sooner you soil test, the sooner you’ll see results. Liming is the most important step in a fertilization program.

What’s going on in Extension?

Nov. 9: MGEV Meeting “Fall Garden Maintenance Program” Open to the public. 6:30 p.m. at the Ag Center. Program begins at 7 p.m.

Nov. 14: What’s a Good Hunting Lease?” UGA Wildlife Specialist Mark McConnell; 7 p.m. at the Ag Center, call (706) 883-1675 to register.

Nov. 20: Troup County Association of Beekeepers 7 p.m. at the Ag Center.

Nov. 21: Troup County Cattleman’s Association: “NRCS and FSA Programs” Meal starts at 7 p.m. Cost $6, call ahead for reservations, (706) 443-7697. The program will start at 7:30 p.m. at the Ag Center.

If you have any questions or concerns, stop by or call the office. UGA has a wealth of information for home and property owners.

Brian Maddy is the ANR Agent for Troup County Extension. The Troup County Extension office is located at 144 Sam Walker Drive, LaGrange. 30240 (706) 883-1675. Monday – Friday 8 a.m. to noon and from 1 to 5 p.m.