Soil sample tips

CLC Labs shares best practices for preparing for a test.

CLC Labs in Westerville, Ohio performs more than 750,000 tests every year on various types of samples. Here are their tips for taking a soil sample:

  • Sample during the first visit of the season, before you apply any fertilizer. If you've recently applied fertilizer, wait six weeks before taking the sample.
  • Remove any turf and thatch before sampling. If you're unable to do that, you can include the turf, thatch and 3 inches of soil.
  • For turf, use a 3-inch deep sample, but for trees or ornamentals, use a 6-inch sample.
  • If you include turf and thatch in your initial test, be sure to continue including them in future tests for consistency.
  • Soil testing requires at least 10 to 12 cores for a typical 6,000 square foot lawn so be sure to take enough samples.
  • Use a zig-zag pattern to get a sample that represents the entire area.