A recent publication in the journal Agriculture Ecosystems and Environment shows the results of maize-based conventional and organic farming systems over the first six years of two long-term field trials in Chuka and Thika in the central highlands of Kenya. The study was carried out by the Research Institute of Organic Agriculture (FiBL) in close cooperation with partners in Kenya.
Both farming systems were compared at input levels of commercial, export-oriented production (high) and at those of smallholder farmers (low). At each level, the farming systems were fertilized with the same amount of nitrogen and phosphorus, the conventional one with farmyard manure and mineral fertilizer, the organic one with compost, ash and rock phosphate. The researchers from FiBL and its Kenyan partners show that after a three-year conversion phase, crop yields from high-input organic systems were similar to those of high-input conventional systems in Chuka and Thika. Despite higher production costs, the profitability of organic farming reached 1.3 to 4.1 times the profitability of conventional systems after the fifth year of conversion to organic due to premium prices. In the low-input systems at Thika, sole maize cropping produced three times higher maize yield in conventional compared to organic, but, when intercropped with beans, the maize yields were similar.