Agriculture is being challenged to maintain profitable farm economics, while meeting the increased product demands of a growing population and responding to increased scrutiny of land and resource management. Agricultural sustainability means addressing economic, environmental and social goals. 4R nutrient stewardship is an innovative approach
to fertilizer best management practices (BMPs) to help achieve agricultural sustainability. The 4Rs imply that there are four aspects to every fertilizer application and it provides an effective framework to assess whether a given crop has access to the necessary nutrients. The four aspects of fertilizer management are interconnected, and none of the four can be right when any one of them is wrong.