Are you actually farming corn though? Over the whole thing? And at the density of commercial operations? Sure, industrial corn operations use a lot of nitrogen

Are you actually farming corn though? Over the whole thing? And at the density of commercial operations? Sure, industrial corn operations use a lot of nitrogen (though they have indeed been shown to be over fertilizing, and a lot of the N from my state ends up in the Gulf), but gardens worked by human hands can be much, much, much more resource efficient at the cost of time and difficulty of automation. With integrated nitrogen fixing plants, better use of mulch (which yes, ties up N at the surface temporarily, but can pay dividends overall), management of water flow etc, I cannot imagine needing that much fertilizer. I garden intensively in Iowa, and I do add a lot of compost when starting new beds (soil is clay) and I top up in the spring, but the older my beds get the fewer inputs they need.