I mean I don't know much about real life farming but do those rows of corns become a different crop when the season changes? Does a winery stop growing grapes when not in season? I mean granted they might not produce anything in winter an might produce less in a wrong season but if you want to make a farm of just corn and make a maze out of it . Dedicate yourself to one crop would be something for roleplayers
Already exists, "All Crops All Seasons" under Mods/Cheats. As for real life... the way Stardew does it isn't *exactly* realistic but it's not too far off. Growing more than one crop in the same field in a year is definitely common, and various plants (or varieties) definitely have their seasons when they will grow and produce (in a given climate). A crop that's planted out of season might grow, but not produce fruit or be harvestable. Stardew simulates this by just having everything die when it goes out of season, as an obvious sign to the player that you won't be able to get anything out of it.