(Can’t you hear time and nomenclature marching forward through the decades with fewer and fewer folks knowing what cannonball-size means and more and more knowing what size watermelon will fit easily into an icebox or refrigerator?) Next down in size are cannonball or icebox watermelons.These are watermelons large enough to feed a crowd, and some of the giant picnic melons could probably feed everyone at a church picnic. At one end of the size chart are the big guys, so-called picnic watermelons.Photo courtesy of Johnny’s Selected Seeds