Coated urea
Coated urea fertilizers are a group of controlled release fertilizers consisting of prills of urea coated in less-soluble chemicals such as sulfur, polymers, other products or a combination. These fertilizers mitigate some of the negative aspects of urea fertilization, such as fertilizer burn. The coatings release the urea either when penetrated by water, as with sulfur, or when broken down, as with polymers.