optimum levels

Asked July 16, 2014, 5:24 AM EDT

I have a soiltest (#643847)and the numbers are do not tell what the optimum, normal or sufficient values should be. For instance the ORGANIC MATTER is 2.3%. What should I expect the normal or good range to be? Same is true for CALCIUM and CEC (whatever that is. No expected range is indicated?) I also don't see any test results for NITROGEN. THANX for your attention

Ottawa County Michigan

1 Response

The organic matter level for a garden we would like to see near 5% or above. For the self mailer reports there is a section at the end of the report that tells you whether your organic matter level is good, and if not it recommends addition of compost. Calcium is not rated in the soil, because if your soil pH is above 6, there is generally sufficient calcium for the plants. CEC (Cation Exchange Capacity) is an unchangeable property of the soil that gives you an indication of the ability of a soil to hold nutrients. The higher the number the more nutrients a soil can hold. Usually the more clay or organic matter a soil has, the higher this number will be. We don't use the number in making fertilizer recommendations however. Because nitrogen is easily leached out of the soil by rainfall, measuring it doesn't help make a proper nitrogen fertilizer recommendation. Because we receive a lot of rainfall in the fall and spring in Michigan, we must replenish the nitrogen each year. Therefore our nitrogen recommendations are based on what you are growing and then you can credit the nitrogen from compost if you are adding it to the soil.