Sulfur-coated urea, or SCU, fertilizers release nitrogen via water penetration through cracks and micropores in the coating. Once water penetrates through the coating, nitrogen release is rapid. The particles of fertilizer may in turn be sealed with wax to slow release further still, making microbial degradation necessary to permit water penetration. The size of fertilizer particles may also be varied in order to vary the time at which nitrogen release occurs. Sulfur-coated products typically range from 32% to 41% elemental nitrogen by weight. The sulfur coating process was originally developed by the Tennessee Valley Authority.

Sulfur Coated Urea Usage:

Sulphur Coated Urea (SCU) fertilizer is a slow-release fertilizer that is made by coating urea with sulphur and wax that increases nitrogen efficiency, improves plant growth and reduces water pollution, compared with water soluble fast-release urea.