SoundGRO is the natural choice fertilizer product for your landscaped areas and vegetable gardens. SoundGRO® is a slow-release fertilizer that contains nutrients and micronutrients that are vital for the healthy growth of your plants. SoundGRO® fertilizer is manufactured at the Chambers Creek Regional Wastewater Treatment Plant and is made from solids that are removed from the wastewater treatment process known as biosolids. SoundGRO® meets the U.S. Environmental Protection Agency's (EPA) highest standards for biosolid safety and is classified as Class A "Exceptional Quality" product. Learn how SoundGRO is manufactured.