Around west central ohio..... Pre emerge herbicide is a must to control water hemp. I plant all 15 in rows to give maximum canopy closing and sun capture for each plant. I cultivate before planting. Decision of 15 vs 30 in rows is dependent on white mold and how prevalent it is in your area. Seed treatments are worth every penny, in my opinion. Plant as early as you can. Bean harvest sunlight and water and turn them into yield. I assume you will have a proper crop rotation cycle to help with below ground pest control. i plant beans the same depth as corn, 1.5 in dp or more depending on moisture. Old timers will tell you that you should see some beans left on top. I plant 160K. I don't know what will work in your area. Seed variety is probably the biggest variable, that you control, in what determines final yield. Do your homework.