The Use of Phosphate Rocks in East Africa: A Review

The use of locally available phosphate rock (PR) has often been proposed as a cheaper alternative to the more expensive superphosphate fertilizers to alleviate severe phosphorus deficiencies that threaten food security in East Africa. Extensive research has therefore been conducted in the region over the years focusing on the PR sources, their reactivity, agronomic effectiveness and the economics of their use and adoption. The agronomic effectiveness varied with the type of PR, the site, seasons and crop. Minjingu PR was the most promising among the PRs for direct application but others such as Panda, Sukulu and Busumbu PR were largely ineffective. The financial returns due to use of PR ranged from negative to positive but in many cases were economically not attractive. The adoption of PR use among farmers was dismal with the unavailability of the PR in the market and high cost, paradoxically being cited as the main constraints to its adoption. To enhance the chances of adoption, it is recommended that participatory approaches to research that involve the targeted beneficiaries especially the PR marketers and smallholder farmers be used.