A motorized spreader assembly facilitates efficient and expedited spreading of seed or fertilizer over a large area. The assembly includes a trailer having a hitch arm. A first bin having a bottom opening is coupled to the trailer. A first disc having a top surface is coupled to the trailer. The first disc is positioned under the first bin whereby the top surface of the first disc is configured for receiving granular material passing through the bottom opening in the first bin. A plurality of fins is coupled to the top surface of the first disc and configured for propelling the granular material outwardly from the first disc while the first disc is rotated. An engine is coupled to the trailer and operationally coupled to the first disc for rotating the first disc.