Effect of agricultural waste as organic fertilizer on yield and soil properties of cocoa (Theobroma cacao L.)

The use of fertilizer particularly for the inorganic fertilizers has increased annually to cope the global demand of crop production. Nevertheless, inorganic fertilizer is expensive and associate with the negative effects to the environment and the soil structure. Alternatively, agricultural waste can be composted and used as organic fertilizer. Although such fertilizer has low nutrient concentration and solubility, it releases nutrients slowly which makes them available for a longer period. Moreover, this agricultural waste such as biomass and manure from plantation and livestock farms are available in abundance. Therefore, this study was conducted to determine the effects of different types of fertilizer treatments as listed; T1 – inorganic fertilizer (control), T2 – chicken manure, T3 – cow manure, T4 – empty fruit bunch and T5 – cocoa pod husk on the production of cocoa mature tree and its soil fertility. The results have shown that organic fertilizers with its consistency application has produce comparable production with inorganic fertiliser and have no differences in the soil chemical properties between the treatments. Hence, this study has clearly demonstrated that agricultural wastes act as organic fertilizers were able to increase crop production and improved the soil fertility in cocoa cultivation.