RE: four season food plot system
The only way to go multi season is to plant multiple plots. Corn, soybeans, clover, winter rye. Even better would be to have an additional 2 or 3 in clover. A 3 year old clover field can be turned under and planted with corn to take advantage of nitrogen fixing. Rotate your plots to minimize disease, weeds, fertilizer, and chemical spraying just like the farmers do.