The most important piece of information from a soil sample analysis of your lawn is the “soil reaction” commonly referred to as the pH. The soil reaction (pH) refers to the relative acidity or alkalinity of the soil and is measured on a scale from 0-14 with 7 being neutral and anything lower being acidic and numbers above 7 indicating alkalinity. Most of our turf grasses prefer soils that are slightly acidic with a pH range of 6.0-6.5. Centipede, requiring less nutrients, is an exception and will perform better in the range of 5.6-6.0. If your soil test results are very far removed from these values you should consider making the recommended changes.
Soil pH has a tremendous impact on the availability of soil nutrients and soil microbial activity. When the soil pH drops below 5.5 or above 8.5 most nutrients (fertilizer) that we apply becomes less available to the turf even if they are in sufficient amounts within the soil. The activity of soil borne microbes is important to the breakdown of thatch and toxic compounds that have been applied for pest management and, in turn, enhance the activity of earthworms, beneficial fungi and bacteria that improve the overall turf rootzone environment. A slightly acidic soil will also deter the incidence of turf pathogens.
A soil analysis may be just what your lawn needs for greater fertilizer efficiency, thatch control, disease management, and overall turf health.
Published January 22, 2007
Dr. Wayne Wells is an Extension Professor and Turfgrass Specialist. His mailing address is Department of Plant and Soil Sciences, Mail Stop 9555, Mississippi State, MS 39762. wwells@ext.msstate.edu