Milorganite is one of the oldest branded fertilizers on the market. It’s composed of heat-dried microbes that have digested the organic matter in wastewater. Milorganite is manufactured by the Milwaukee Metropolitan Sewerage District. The District captures wastewater from the metropolitan Milwaukee area, including local industries such as MillerCoors.
Using large-scale processes that mimic nature, microbes digest the nutrients found in the water. The cleaned water is returned to Lake Michigan while the microbes are kiln-dried into small pellets