Economic Assessment of Napier Grass Production Using Different Fertilizer Combinations under Smallholder Farming Conditions in the Central Highlands of Kenya

Aims: The objective of the study was to evaluate the cost-effectiveness of using different fertilizer combinations to improve Napier grass production within the smallholder farms. Study Design: The experimental design was a Randomised Complete Block Design (RCBD) with three replicates per treatment. The treatments were: Di-Ammonium Phosphate (DAP); rabbit (Oryctolagus cuniculus) manure; rabbit manure plus rabbit urine; DAP plus Calcium Ammonium Nitrate (CAN); DAP plus rabbit urine; Control; and Conventional method. Place and Duration of Study: The study was done in Embu County, Kenya from March 2015 to January 2016. Methodology: The economic analysis to determine the most cost-effective fertilizer was done using gross margins and cost-benefit ratios approach. Results: Rabbit manure plus urine had the highest cost of production averages at US$.154 8.13 per year at p<0.05 while the conventional method was US$ 494.59 at p<0.05. The study revealed that the most cost-effective fertilizer in Embu County was DAP plus rabbit urine treatment under ‘‘Tumbukiza’’ pits. Conclusion: The projections are that by the end of the second cropping year, the treatment top-dressed with either rabbit urine or CAN would be having higher gross margins since the initial cost would have been recovered. Farmers in Embu County are encouraged to integrate the use of both organic and inorganic fertilizers to achieve high production in a cost-effective way.