If you are needing a good amount of special fertilizers, and have a hard time finding them bagged at Lesco, Home Depot, etc., try an agricultural supplier near you. Chances are that similar ammonium sulfate formulation is needed on farms in your area. They will have formulations in bulk, but will usually sell by the 100# in bags filled on the spot. Often will be cheaper, and usually makes it a lot easier to find.
Just do not use the ag supplier for pesticides. Ag herbicides are cheaper than equivalent turf formulations, but are labelled for ag use. If you use these on turf, you're opening yourself up to heavy fines.
North central Indiana
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