This isn't really an impressive test; growing corn is an extremely well-documented solved problem, the sort of thing that we already know LLMs excel at. An LLM that couldn't reliably tell you what to do at each step of the corn-farming process would be a very poor LLM.

This seems like something along the lines of "We know we can use Excel to calculate profit/loss for a Mexican restaurant, but will it work for a Tibetan-Indonesian fusion restaurant? Nobody's ever done that before!"