Strongly acidic soil is a major problem in Taiwan. The application of organic fertilizers is an important practice in increasing the productivity of such soils. However, the transforma- tion and availability of phosphorus in the soil will be more complex if organic fertilizers are used in strongly acidic soils. This paper discusses the effect of using composted animal manure on the availability of nitrogen and phosphorus in strongly acidic soils in Taiwan. The develop- ment of phosphocompost and its application to strongly acidic soils are also discussed.