Step 1 - Test Your Soil!
If you are planning a new hopyard or an expansion of an existing hopyard, soil sampling is the first step to success. Hops are hungry plants! Take one sample every acre of planned hopyard and plan your fertilizer based on the results of those tests. Consult University of Wisconsin Extension publication A2100 for more details.
Also, Grow More Hops would be glad to provide you with soil sample bags, postage-paid analysis by a reputable soil testing lab and a hop-growing oriented interpretation of the report. There may be a fee for this service. Contact Lee at firstname.lastname@example.org for details.