An Efficacious Supplementary Fertilizer Formulation from Agricultural Farm Biomass

Though composting is a practical method of recycling plant macronutrients in organic matter, it is impractical with biomass like sisal leaf wastes, horns, hooves and feathers that take long to decompose. This biomass is therefore ignored; causing waste disposal hitches and yet are rich in plant macronutrients (nitrogen, phosphorous, potassium and calcium). This study set out to use them to formulate a supplementary fertilizer (SF). Samples of maize cobs and stalks, sugarcane bagasse, cattle hooves/horns and sisal leaf biomass were, taken through wet digestion before laboratory analysis for levels of nitrogen, phosphorous, potassium and calcium using standard procedures. Different formulations were obtained by mixing solvent digested hooves/horns (HD) with lye pre-treated sisal leaf biomass (CASD) giving ratios HD:CASD 0:1 (SF0), 1:1 (SF1), 2:1 (SF2), 3:1 (SF3), 1:2 (SF4) and 1:0 (SF5) that had varying pH values. Formulation SF1 (ratio 1:1 and pH 8.0) was used during fieldwork to evaluate the formulation's efficacy on the rate of growth, pest control and crop (maize) yield. Four sets of maize plots under varying fertilizer treatments or schedules (SF1/SF1, SF1/CAN, NIL/CAN and DAP/CAN) were replicated three times within the study area (Lugari Kakamega county, Kenya). There was no significant difference (p = 0.273) noted in the yields between the use of the formulation, SF1 and the commercial fertilizers DAP/CAN schedule. The stalk borer attack on the stems, fruits and tassels of the maize in plots that had nil fertilizer schedule (control) was in the range 60-75% compared to 10-15% and 4-7% in those where the supplementary fertilizer (SF1) and DAP/CAN were respectively applied. The findings of this study showed that the agricultural biomass can be blend into an effective and efficient supplementary fertilizer with sufficient levels of plant macronutrients (N, P, K and Ca). The approaches used in material pretreatment shorten the period of decomposition compared to the traditional composting methods.