Sulfur‐coated Fertilizers for Sugarcane: II. Release Characteristics of Sulfur‐coated Urea and KCl

Abstract

Nitrogen release from sulfur‐coated urea and K release from S‐coated KCl were examined by several techniques under field conditions in three south Florida sand soils in order to assist in the interpretation of plant response data and to provide insight into the use of three slow‐release fertilizer materials. Decreased thickness of S coating, higher temperatures and higher moisture generally favored nutrient release. However, considering the range of field conditions involved in the studies, variations in N and K release were comparatively small. Release was rapid during the first 6 months, averaging 70–80% of that applied, but was much slower thereafter.