A method may be employed to produce a fertilizer granulate comprising an ammonium salt and, as a filler material, limestone, dolomite, and/or magnesite. At least a proportion of the limestone or dolomite or magnesite is at least partially calcinated prior to use in the fertilizer granulate. A targeted adjustment of the reactivity of the filler material may occur by its degree of calcination and/or its calcite proportion. If, for example, dolomite is used as a filler material, the calcination results in separation of carbon dioxide from the mineral. This calcination is a two-stage process in which the dolomite is first converted to periclase (MgO) and calcite (CaCO3), and the calcite is also converted by decomposition and release of carbon dioxide only at a higher temperature.