Development and Dissemination of 4R Nutrient Stewardship Knowledge to Support Crop Production Intensification in Western Kenya

The lack of appropriate site-specific nutrient management recommendations is one of the key underlying factors for low crop productivity in sub-Saharan Africa (SSA). The 4R Nutrient Stewardship Framework, developed by the fertilizer industry, aims to provide the context for efficient nutrient management focusing on four central components: applying the right fertilizer source, at the right rate, at the right time in the growing season, and in the right place. Implemented in collaboration with national and county level agricultural stakeholders, the current project in Western Kenya focused on demonstrating the impact of various 4R techniques, including site- and crop-specific fertilizer recommendations, on crop productivity and farm profit.

In the first three years (2013 to 2015) of the project, pilot 4R demonstration sites were established, 4R training materials were developed, and farmers and extension officers were trained. In the past year, up scaling of 4R learning sites, evaluation of the role of balanced nutrition in sustainable yield intensification, and monitoring and evaluation of adoption of 4R practices among farmers were targeted.

Analysis of nutrient omission yield data across six consecutive seasons in 24 on-farm sites showed that balanced nutrition with nitrogen, phosphorous and potassium (NPK) resulted in a higher grain yield and lower variability in yields compared to the other treatments in which one of the nutrients were omitted. This illustrates the importance of balanced nutrition for sustainable crop production intensification. So far, the project has facilitated training of 3,000 farmers on improved crop and nutrient management practices through collaboration with the Siaya County Department of Agriculture (SCDA). A monitoring and evaluation exercise was conducted among pilot farmers involved in the project. The survey indicated high adoption of the right source and right time components of the 4R Nutrient Stewardship, but lower adoption of the right rate of fertilizer application. A majority of the farmers attributed this to the lack of adequate resources to purchase required quantities of fertilizers and difficulties gaining access to government-subsidized fertilizers. This illustrates that further interventions may be required at various levels to enable farmers in the study area to fully implement the correct nutrient management practices based on 4R Nutrient Stewardship.