Agronomic Services — News ReleaseFOR IMMEDIATE RELEASE
MONDAY, JUNE 7, 2010
Contact: J. Kent Messick, field services chief
NCDA&CS Agronomic Division
Soil testing helps landscapes live long and prosper
RALEIGH—If you are planning to renovate an existing landscape or install a new one, the first and most crucial step is soil testing. Once you know a soil’s pH and nutrient content, you can custom-prepare that soil so the new landscape planting will be more likely to thrive.
Phosphorus levels and soil pH are among the most common problems, said Charles Mitchell, regional agronomist with the N.C. Department of Agriculture and Consumer Services.
“Soils in newly cleared areas are often low in phosphorus,” Mitchell said. “And soil pH almost always needs adjusting, yet many landscapers never bother to soil test. Usually they apply a standard rate of lime and a basic, balanced fertilizer without bothering to find out what is actually needed.”
Although soil fertility problems can be adjusted after plants are installed, it is much easier and much more effective to do it beforehand. Soil testing is insurance. It provides specific information on how to transform a site into an ideal site for the plants you want to grow.
Ted Mullen of Mr. Landscape Design Build Inc. in Bunn considers soil testing essential to the success of his 15-year-old business. “I started out with the goal of doing high-end residential landscaping,” Mullen said. “I found myself dealing with eroded, red clay that was very much in need of lime. It didn’t take long to find out that getting the soil pH right was the first step to a good-looking yard.
“If the soil is not at the right pH, the nutrients are not going to be available,” Mullen said. “It won’t do much good to put out fertilizer if the pH isn’t corrected first. It’s a waste of money, and it can cause environmental harm. When I landscape lake-front property, I want to make sure the water stays clean.”
Soil testing is the only way to know for sure whether lime and nutrients are needed and, if so, exactly how much and in what combination. When recommended by a soil report, lime should be thoroughly mixed into the soil. It usually takes several months for it to alter soil pH. This adjustment takes much longer for established or renovated plantings where lime can be applied only to the soil surface.
Landscapers who skip soil sampling may just assume that lime is always necessary in areas with clay soil. That is not a safe assumption, especially if homeowners have been applying lime for years without soil testing. Mullen has encountered situations that actually required him to try to lower the pH before renovating a lawn.
Mitchell recommends that anyone paying for landscaping services stipulate that the provider collect soil samples and follow the recommendations given in the report. These recommendations are very specific. In addition to any lime or micronutrients needed, they suggest an appropriate fertilizer rate and grade, which is a unique combination of nitrogen, phosphorus and potassium.
“If soil issues aren’t addressed at the beginning, you’ll be fighting an uphill battle from then on,” Mitchell said. “At the beginning of a project . . . that’s when soil sampling really proves its worth.”
North Carolina residents have access to free soil testing through the NCDA&CS Agronomic Division. Detailed information on sampling techniques and preferred shipping methods are available online at www.ncagr.com/agronomi/sampleinfo.htm.