When it comes to farming and gardening, it always pays to think ahead. Especially when it comes to your soil.
Rather than applying fertilizers and other soil amendments your plants may or may not need, you should conduct a soil test to find out what you already have and what you need to create a healthier soil and a better return on your fertilizer investment.
By testing and applying organic fertilizers as needed in the fall of the year, we can replenish what our summer crops have used and give soil microorganisms time to balance the soil nutrients before next year’s crop.
Where to Get a Soil Test Kit
Soil Sample Test Kits are available free of charge and can be picked up from the Cooperative Extension Office in your county. Click here to locate an office for your NC county.
The kit contains detailed instructions on how to collect a soil test sample and includes two soil sample boxes. The test kit, analysis and recommendations are free, but you will have to pay mailing costs to send your samples to the test lab in Raleigh, NC.
For information on soil tests in South Carolina and to locate an office for your SC county, visit the Clemson Cooperative Extension.
Outside the Carolinas
Check with your state’s Agricultural Office for the correct Department to contact.
From April through November, routine North Carolina Department of Agriculture & Consumer Services (NCDA&CS) soil tests are provided at “no direct cost” to NC residents through funding derived from a statewide fee on commercial fertilizer.
From December through March however, a peak-season fee of $4 is charged for the processing of all soil samples. So not only is this a good time to test for the health of your soil, it’s a good time to test for your budget!
There are four steps to a soil test:
- Taking the soil sample (see detailed instructions with kit)
- The soil analysis (conducted by NCDA&CS)
- Interpretation of the results (provided by NCDA&CS)
- Fertilizer recommendations (listed on your report)
The NCDA&CS test will give you a detailed soil analysis covering:
- Levels of major plant nutrients, including phosphorus, potassium, calcium, magnesium & sulfur
- Levels of plant micronutrients, including copper, manganese & zinc
- Levels of sodium
- pH and acidity
- Soil class
- Percent base saturation
- Percent humic matter
- Cation exchange capacity
- Weight-to-volume ratio
The NCDA&CS test also gives you site-specific fertilizer and lime recommendations that can:
- Optimize crop yields
- Improve efficiency
- Reduce cost of production
- Conserve natural resources
- Protect the environment by minimizing excessive use of fertilizers, particularly nitrogen
Interpreting a soil test’s results may seem daunting, but you don’t need to be a soil scientist to benefit from your test report.
The goal of the test result is to help you build the correct balance of nutrients in the proper amounts for optimum plant growth and the NCDA&CS test report makes it easy.
For example, soil pH is one of the most important soil properties that affects the availability of nutrients to plants, so pay special attention to bringing your soil’s pH into the optimum range.
Macronutrients, such as nitrogen (N), phosphorus (P), potassium (K), magnesium (Mg) and sulfur (S) tend to be less available to plants in soils with low pH. Micronutrients such as boron (B), copper (Cu), iron (Fe), chloride (Cl), manganese (Mn), molybdenum (Mo) and zinc (Zn) tend to be less available to plants in soils with high pH.
Your soil test results will reveal these and other potential issues.
For a bit more insight, take a look inside North Carolina’s soil testing lab in Raleigh.
A little investigative work now, will pay off with higher crop yields later. So get that soil test today!
Written by Mary Roberts
PCG Member Mary Roberts, along with Ray Tarlton, are owners and managers of Windcrest Farm, a USDA Certified Organic farm and greenhouse in Monroe, NC .