Ask the Master Gardener

What is a soil test?

A soil test analysis is one of the most important tools a home gardener can use in creating a healthy soil environment for your garden or yard. The report can determine the soil pH and level of nutrients present in the soil.  It can be done at anytime of the year, but ideally should be done before you fertilize existing plants and turf grass, or a few months before you plan on starting your garden. Soil testing allows you to customize your fertilizer and lime needs based on a) type of plants and b) nutritional deficiencies.  It also can save you money, and protect the environment by avoiding over-fertilization hazards in leaching and run-off.

How do I collect a soil sample for testing?

For an accurate test, collect a "representaive sample", which means collecting 12 or more core samples and combining them into one composite sample. For garden soil, the samples should include soil taken from the surface to a depth of 6 to 8 inches down. For lawns, samples should be taken only from a depth of only 3 to 6 inches. Use a soil auger, spade, shovel, or garden trowel. When using a spade or shovel, take a thin slice from the side of a "V"- shaped hole. Place the samples in a clean plastic bucket and mix them thoroughly. Bring a minimum of 2 cups of soil per sample to your county Clemson Extension office (addresses and phone numbers are under the About Us tab). It will be "bagged and tagged" and labeled with the type of plants you wish to grow or fertilize, then taken to the Agricultural Service Laboratory at Clemson. The soil will be analyzed, and you will be sent (via either email or U.S.mail) the Soil Test Report in a few weeks.