We plant our bigger patch with the field corn. It's easy to get the N on that way, but you have to not forget to skip the roundup.   My neighbor killed half his last summer.  For weed control, use a rotor tiller and the kids that are selling it.   I went with a low population last year and got 2 ears on every stalk.  The second was ready about 5 days later.   I think it was 24,000.