Patent 7771505 was granted and assigned to Agrium on August, 2010 by the United States Patent and Trademark Office.
A controlled release fertilizer composition and methods to produce the controlled release fertilizer composition are described. The controlled release fertilizer composition comprises a water soluble fertilizer core that is coated with a polymeric layer, intermediate layer, and a sulfur layer. If desired, the sulfur layer can be coated with an outer water-insoluble layer.