It isn't necessary to drill a hole in the cabbage to hang it. Take a stiff wire (old coat hanger) and push it though the core. Bend a small 90 at the end to prevent the head from coming off, and then bend a loop at the top to attach rope. I try to give my birds at least one head a week but I no longer hang it since it's usually gone in less than an hour. I just cut it in quarters and toss it into the coop.