I use a very long nail; the kind often used to hold gutters to fascia board. I have a shepherd's hook in the yard. There's a piece of poly-cord with a loop tied into each end. One loop is attached to the nail in a kind of slip-knot; loop the cord around the shaft of the long nail and through the looped loop so anything pulling on the nail makes it tighter. Whoops! Before you attach the poly cord to the nail, push the nail into the core of the head of cabbage. Turn it over and use the head of cabbage as a battering ram with the nail head pressed aginst something solid. Pound it deep into the cabbage. Then slip the loop slip-knot over the head of the nail. I have the cord set to hold the cabbage above the chickens' heads by about four inches or so, so they have to jump to pull off a beakful.