In today’s agricultural economy it is tempting to take a few shortcuts and not purchase inputs or services that were utilized in the past. Growers need to make the best use of their financial resources, but care must be taken not to cut inputs that can make money. As growers consider their crop nutrition needs it is tempting to forgo something as basic, but important, as soil testing.
Soil testing allows the grower to determine the current condition of the soil, including imbalances, deficiencies, and excesses. It also helps identify how much nutrition is already available in the soil so that fertilizer applications can be optimized. A multi-year testing program allows the grower to monitor changes in the soil over time.
Planning a soil sampling program requires the grower to know the field. A good starting point for planning a sampling plan is a soil survey map that identifies different soil types in that field. The grower also needs to identify areas of the field that are unique, such as a sandy knoll or wet depression that the soil survey map doesn’t identify. A soil sample should be representative of a similar section of the field, and any unique areas should be sampled separately. The number of acres represented by a soil sample will vary by field but should generally not exceed 20 acres per sample. The soil test report is only as good as the sample that is sent to the lab.
The soil test report can be used to develop a complete nutrient management program for a field, including soil amendments to adjust nutrient imbalances as well as determine the fertilizer application needs for the crop. Using products that can be mixed to address the needs of a field will provide the best opportunity for economic return.
Yes, soil testing does cost money — around $25 per sample for a complete test that includes soil characteristics, nutrient levels and base saturation. If, for example, one soil sample represents 20 acres in a field and the field is sampled every three years, the cost of soil sampling averages out to be about $0.41 per acre per year. The information gained from that $0.41 can guide a grower in making crop nutrition decisions that will address the needs of the crop and avoid excesses or deficiencies.
If you are not familiar with proper soil sampling procedures, the Responsible Nutrient Management Foundation offers a Soil Sampler Field Certification — kind of a soil sampling 101. Certification will provide soil samplers with the knowledge to provide consistent samples to their labs, maximizing the value of results. Check it out at http://www.rnmf.org/soil-sample-certification/.
Finally, don’t overlook your resources. Companies have whole divisions with people specifically trained, educated, and experienced to help you make the best decision based on your farm’s soil data. The time has come to boldly ask us to earn our pay and put our skills to use on your farm. Sound agronomic advice combined with our trusted crop nutrients can provide a balanced fertilizer program that gives your crop a chance to keep you profitable.