- Soil testing is a useful and relatively inexpensive management tool for growers to assess crop nutrient levels in their fields.
- Proper methods and timing of soil sampling help ensure reliability of test results for making informed decisions related to soil inputs such as fertilizer and lime.
- Standard soil tests typically evaluate pH, buffer pH, organic matter, cation exchange capacity, phosphorus, potassium, calcium, magnesium and base saturation.
- Micronutrient soil testing alone is generally not a reliable tool to predict potential micronutrient deficiencies. Tissue testing, soil properties, and growing conditions together are a more complete diagnostic approach.
- Critical levels of nutrients (the point below which crop yield may decrease quickly) and crop removal rates are useful for determining the rate and frequency of fertilizer application to a field.
Growers must efficiently manage field inputs while reducing the risk of yield losses to maximize profitability season after season. Fertilizers are significant variable costs in production, and tools are available to assess their need. This Crop Insights will describe best management practices for soil testing, report interpretation, and assessing fertilizer needs for crops in North America.