Declining land productivity is a major problem facing smallholder farmers in Kenya today. This decline is as a resultof reduced soil fertility caused by continuous cultivation without adequate addition of manures and fertilizers. Lowsoil fertility is one of the greatest challenges facing farmers in the central highlands of Kenya. A farmers' participatory trial was established in Meru South District, Kenya in 2000 to investigate feasible soil nutrient replenishmenttechnologies for poor resource

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... mallholder farmers. Results across seven seasons indicate that sole tithonia gavethe highest grain yield followed closely by tithonia with half recommended rate of inorganic fertilizer with 6.4 and 6.3 Mg ha-1respectively. The control treatment gave the lowest yield of 2.2 Mg ha " across the seasons. Theintegration of organic and inorganic nutrient sources of N gave higher maize grain yield as compared to the soleorganic materials in all seven seasons. Economic analyses indicate that on average tithonia with half the recommended rate of inorganic fertilizer recorded the highest net benefit (US$ 787.2) whereas the control treatment gavethe lowest benefit (US$ 271.7). On the other hand the recommended rate of inorganic fertilizer gave the highest