4R Nutrient Stewardship represents an innovative approach to fertilizer best management practices (BMPs). The 4Rs imply there are four aspects to every fertilizer application and it provides a framework to assess whether a given crop has access to the necessary nutrients. Asking “Was the crop given the right source at the right rate, at the right time, and in the right place?” helps identify opportunities to improve fertilizer efficiency and prevent nutrient movement from each field.
