Well I didn't grow this and don't plan on growing them but I have to share this picture. This is a cabbage pile at the local farmers market, these things are bigger than a basketball. The coffee cup in the picture is a medium size, for reference. I was pretty blown away by these.
I remember seeing a picture of a fellow's cabbage patch up in the Mattanooska Valley in Alaska. Between the long hours of daylight in the summer there and the volcanic soil his cabbages were as tall as his 5-year-old daughter.