Factors Affecting the Rate of Release of Fertilizer from Capsules1

Synopsis Capsulation of fertilizer with polyethylene film gave significant increases in yield of corn and recovery of N and P. Rate of release of fertilizer from capsules was directly related to temperature, number of pinholes per capsule, and vapor pressure lowering of water by the fertilizer, but, generally, was independent of the presence of the crop and of soil texture, soil moisture between 25 and 100% field moisture capacity, and leaching of the soil.