A method of inhibiting nitrification processes, phosphate fixation processes, urease activities, and combinations thereof, comprising the step of applying to soil an anionic polymer mixed with an ammoniacal solid, liquid, or gaseous fertilizer, the polymer being at a level of from about 0.01-10% by weight, based upon the total weight of the polymer/fertilizer product taken as 100% by weight, wherein the anionic polymer comprises at least four repeat units distributed along the length of the polymer chain, said at least four different repeat units including at least one each of type B, type C, and type G repeat units, said type B repeat units selected from the group consisting of repeat units derived from substituted and unsubstituted monomers of maleic acid and/or anhydride, fumaric acid and/or anhydride, mesaconic acid and/or anhydride, mixtures of the foregoing, and any isomers, esters, acid chlorides, and partial or complete salts of any of the foregoing, wherein type B repeat units may be substituted with one or more C1-C6 straight or branched chain alkyl groups substantially free of ring structures and halo atoms, and wherein the salts have salt-forming cations selected from the group consisting of metals, amines, and mixtures thereof, said type C repeat units selected from the group consisting of repeat units derived from substituted or unsubstituted monomers of itaconic acid, itaconic anhydride, and any isomers, esters, and the partial or complete salts of any of the foregoing, and mixtures of any of the foregoing, wherein the type C repeat units may be substituted with one or more C1-C6 straight or branched chain alkyl groups substantially free of ring structures and ha-lo atoms, and wherein the salts have salt-forming cations selected from the group consisting of metals, amines, and mixtures thereof, said type G repeat units selected from the group consisting of repeat units derived from substituted or unsubstituted sulfonated monomers possessing at least one carbon-carbon double bond and at least one sulfonate group and which are substantially free of aromatic rings and amide groups, and any isomers, and the partial or complete salts of any of the foregoing, and mixtures of any of the foregoing, wherein type G repeat units may be substituted with one or more C1-C6 straight or branched chain alkyl groups substantially free of ring structures and halo atoms, and wherein the salts of the type G repeat units have salt-forming cations selected from the group consisting of metals, amines, and mixtures thereof, said repeat units being randomly located along the polymer, at least about 90 mole percent of the repeat units therein are selected from the group consisting of type B, C, and G repeat units, and mixtures thereof, said anionic polymer containing no more than about 10 mole percent of any of (i) non-carboxylate olefin repeat units, (ii) ether repeat units, and (iii) non-sulfonated monocarboxylic repeat units, said repeat units including at least one each of a maleic, itaconic, and sulfonate repeat unit. said at least four different repeat units including at least one each of type B, type C, and type G repeat units, said type B repeat units selected from the group consisting of repeat units derived from substituted and unsubstituted monomers of maleic acid and/or anhydride, fumaric acid and/or anhydride, mesaconic acid and/or anhydride, mixtures of the foregoing, and any isomers, esters, acid chlorides, and partial or complete salts of any of the foregoing, wherein type B repeat units may be substituted with one or more C1-C6 straight or branched chain alkyl groups substantially free of ring structures and halo atoms, and wherein the salts have salt-forming cations selected from the group consisting of metals, amines, and mixtures thereof, said type C repeat units selected from the group consisting of repeat units derived from substituted or unsubstituted monomers of itaconic acid, itaconic anhydride, and any isomers, esters, and the partial or complete salts of any of the foregoing, and mixtures of any of the foregoing, wherein the type C repeat units may be substituted with one or more C1-C6 straight or branched chain alkyl groups substantially free of ring structures and ha-lo atoms, and wherein the salts have salt-forming cations selected from the group consisting of metals, amines, and mixtures thereof, said type G repeat units selected from the group consisting of repeat units derived from substituted or unsubstituted sulfonated monomers possessing at least one carbon-carbon double bond and at least one sulfonate group and which are substantially free of aromatic rings and amide groups, and any isomers, and the partial or complete salts of any of the foregoing, and mixtures of any of the foregoing, wherein type G repeat units may be substituted with one or more C1-C6 straight or branched chain alkyl groups substantially free of ring structures and halo atoms, and wherein the salts of the type G repeat units have salt-forming cations selected from the group consisting of metals, amines, and mixtures thereof, said repeat units being randomly located along the polymer, at least about 90 mole percent of the repeat units therein are selected from the group consisting of type B, C, and G repeat units, and mixtures thereof, said anionic polymer containing no more than about 10 mole percent of any of (i) non-carboxylate olefin repeat units, (ii) ether repeat units, and (iii) non-sulfonated monocarboxylic repeat units, said repeat units including at least one each of a maleic, itaconic, and sulfonate repeat unit.