Abstract: An improved distribution tower for weighing and mixing particulate material such as chemical fertilizer has a plurality of storage containers therein for separate storage of various particulate materials and utilizes a combined weighing and mixing bin which is positioned below the storage containers to receive material therefrom, the bin being provided with an upright central auger for mixing and blending the material before discharging the material through a discharge duct at the base of the bin. The bin is also provided with a weight measuring scale to weigh quantities of material added thereto from the storage containers so as to permit predetermined fertilizer compositions to be formulated. In one embodiment the auger apparatus has radial paddles to better mix the material. A second embodiment utilizes a combined weighing and mixing bin wherein a funnel-like configuration of spaced-apart baffle plates is carried by the bin and intercepts and redistributes material discharged by the auger.