OFRF-funded Research Supports the Creation of a Nutrient Budget Tool for Organic Grain Farmers


Increasingly, we are recognizing the value of a plant-based diet for human health and nutrition. But, have you ever thought about what fuels a plant? This is a question that is constantly on the minds of farmers, particularly organic producers who are prohibited from using synthetic fertilizers to feed their crops. Rather, organic farmers rely on organic inputs, such as green manures—plants that are grown and then intentionally plowed into the soil to add nutrients—to build soil health and feed beneficial soil life.

Green manures are a particularly important organic amendment for organic grain farmers in the Canadian prairies. However, due to a lack of organic extension resources, adoption and effective management of green manures by organic farmers in this region is poor. Moreover, nutrients from organic inputs are released slowly and are not effectively captured by traditional soil tests, which were developed for conventional farming systems. The lack of appropriate soil tests for organic farmers can make it difficult for them to determine which organic amendments they should use.

To address these challenges, OFRF funded researchers from The Prairie Organic Grain Initiative and the University of Manitoba to educate farmers on the proper use of green manures and to develop a tool specifically designed to measure the nutrient needs of organic farms. In addition, the project addressed the lack of robust organic extension services in the region by training local agronomists in organic green manure practices.

To overcome the limitations of soil tests developed for conventional farming systems, researchers from the University of Manitoba created a green manure bioassay protocol that is designed to measure the slow-release of nutrients from organic inputs, allowing farmers to better assess the nutrient profile of their soils. A total of 14 agronomists were trained to use the green manure bioassay and they visited over 50 organic grain farms to collect plant and soil samples. By combining the results of these bioassays with field history, the agronomists were able to develop a nutrient budget specific to each farm field.

In addition to farm-specific nutrient budgets, data from individual farms is being pooled to create a large database that can be used to explore relationships between green manure management, soil nutrients, soil type, and grain yield and quality. Ultimately, this nutrient budget tool will allow farmers to determine the best management practices for their farm by running multiple crop rotation and nutrient management scenarios.

View the Final Report here.

Find more information on the nutrient budget tool here.