Guidelines for Developing Site-specific Plant Nutrition Plan Based on Best Management Practices

The fertilizer industry, as well as the farmers it serves, recognizes the importance of managing nutrients correctly both for maximum profitability and improved agricultural sustainability. Excess fertilizer leaches into waterways as well as costing growers extra money. Too little fertilizer has an obvious impact on yields and can also contribute to soil erosion by not supporting enough plant life to anchor soil in place.

Without fertilizer, farmers cannot maintain the kinds of yields necessary to feed the world’s burgeoning population. While advances in genetics and biotech seed industries can produce plants with the potential for greater yields, optimum nutrient levels are necessary for those varieties to realize their full genetic potential. Recognizing the need to provide solutions based on sound science, The Fertilizer Institute, The International Plant Nutrition Institute, The Canadian Fertilizer Institute, The Conservation Technology Information Center and the Association of American Plant Food Control Officials have all endorsed the 4Rs of Nutrient Stewardship. The 4R system was also just recently endorsed by the USDA-NRCS in the new 590 Nutrient Management Standard.

The 4Rs refer to applying the Right Source at the Right Rate at the Right Time in the Right Place. Applying just the right amount and type of nutrients needed by a specific crop at the right time in its growth cycle in only the areas where they are needed maximizes yield, reduces costs and minimizes run-off of excess nutrients, thus benefiting the environment. The 4Rs provides a guiding principle for farmers, fertilizer companies, environmental experts and crop advisors to develop a site-specific nutrition plan based on sound scientific research and cropping methods that adhere to Best Management Practices (BMPs). Economic, environmental and social goals are determined by key stakeholders, who also determine the measures of success.

Regulatory pressure to reduce the use of fertilizers is increasing as agencies such as the U.S. Environmental Protection Agency and The National Academy of Sciences are increasingly citing agricultural nutrient inputs as the source of large amounts of pollution in major waterways. Legislative action to limit fertilizer use is also happening at the state and local levels.

Adhering to the 4Rs principles can help improve agricultural productivity while minimizing the impact to the environment. Keeping nutrients within a field’s boundaries by targeted applications at the root zone or via foliar feeding, increasing production on existing farmland and thus protecting natural ecosystems, and matching the amount of nutrients applied to the crop’s needs are just a few of the goals of the 4R nutrient stewardship.