CHARLOTTE – Soil pH is an indication of soil acidity or alkalinity of soil and is measured in pH units. The pH scale goes from 0 to 14 and pH 7 is the neutral point. From 0 to 7 soil is more acidic, the lower the number the more acidic. From 7 to 14, soil is more alkaline, the higher the number the more alkalinity.

The effect of soil pH is great on the solubility of minerals and nutrients. 14 of 17 essential plant nutrients are found in the soil.  Before a nutrient can be used by a plant it must be dissolved. Most minerals and nutrients are more soluble in acidic soils than in neutral or slightly alkaline soils.

There are two methods of testing that are commonly used. The most accurate method is using a pH meter. The second method is simple and easy but less accurate and consists of using certain indicators or dyes. Soil sampling kits are available at your local nursery and garden stores. If you need to test a large area such as your lawn it is good to take several samples because pH can vary significantly.

Once you determine the pH you may need to add more lime to your soil to make it less acidic while some plants thrive in slightly more acidic soil such as azaleas, rhododendrons and blueberries. The pH level in your soil also effects the beneficial microorganism bacteria that is necessary to decompose organic matter.

For more information contact your local garden center, your local Cooperative Extension department or call Metrolina Mulch at (704) 888-1822. You can also visit our website www.metrolinamulch.com.