I don't have much room for iris. I live on a city lot in the suburbs of Detroit and although it is a corner lot, I have over 300 daylilies planted. I have absolutely no grass in my backyard. Now, if I lived about l80 miles north where our small l bedroom cottage is, I would have more room, as the lot size is about l/4 acre. Not sure how well iris would grow in zone 4 though. Would love to get out of the city and move up there.