Soil Testing

By   October 8, 2015

Soil testing is an inexpensive service that can save a lot of time, trouble, and money. Primarily designed for farmers, your lawn can benefit from the same professional analysis. For just a few dollars, a test lab can tell you exactly what’s missing from your soil and take the guesswork out.

Soil Testing Kits

Reports vary, but most soil testing results will include:

  • A pH measurement. Soil pH is a measure of how acidic or alkaline your soil is, which affects nutrient availability. The pH scale ranges from 0 to 14, with 7 as neutral. Numbers less than 7 indicate an acid condition, while numbers greater than 7 indicate an alkaline soil. Most grasses like the pH to be close to neutral, but New England soils, ran, and native plants tend to push the pH towards the acid range.
  • Primary nutrients. These are the N, P, K basics that are listed on the fertilizer bag. N, P, and K stands for Nitrogen (N), phosphorus (P) and potassium (K) which are needed in fairly large quantities compared to the other nutrients.
    Secondary nutrients: Calcium (Ca), magnesium (Mg) and sulfur (S) are secondary nutrients which are required by grass in lesser quantities than the primary nutrients. Zinc (Zn) and manganese (Mn) are micronutrients which are required by plants in very small amounts.
Typical soil testing kit

Typical soil testing kit

For a good soil testing, you need to take a good sample….the test won’t be accurate if you happen to pick a spot that your dog watered last night. Using a trowel, take 4” deep slices or cores from 6 to 10 locations. To get a good sample, mix several samples from different location together in a clean bucket or sample bag (plastic, not paper). Make sure that everything is super-clean, and don’t use your hands.

For lawns, the most important test is pH. If you get the pH in to the recommended range, existing nutrients from the soil will become available to you lawn and your primary nutrients will be much more effective. Lawns are heavy feeders, so expect your test to almost always show deficiencies of the basic N, P, K nutrients.