A coating is applied in one or more layers on a granular material, such as a granular fertilizer material or the like. The coating may include a diisocyanate in either pure form or partially polymerized form, a polyol or polyol mix, and optionally a wax. The polyol or polyol mix may be, for example, a polyester polyol, a polyether polyol, or combinations thereof. In some examples, the polyol or polyol mix may be an aliphatic glycerine initiated polyether polyol, an aliphatic amine initiated trifunctional polyol, castor oil or castor oil derivative, or ethylene diamine that has been propoxylated or ethoxylated, and combinations thereof. The coating is reacted on the granular material.