If you have a child who really wants to be a cabbage for Halloween, then you can make a creative costume with a few ordinary materials -- many of which you may already have in your craft supply. Ask your child to dress completely in green. Build on the costume from this base.
Blow up a green inflatable pool ring, and place it around your child's waist. Secure the ring to your child's body with packing tape.
Crumble your green wrapping paper or art paper. Gently crush sections in your hand as you work your way down the roll. This creates the look of the cabbage leaves.
Begin wrapping the roll of green wrapping paper or art paper around the ring and your child's body. Attach the paper to the ring with clear packing tape. You may need to trim the length of the paper before you start if the paper covers up your child's knees.
Continue wrapping the paper loosely around your child until it forms a thick, round ball. Snip off the paper from the roll, and tape it to the side with a bit of packing tape.
If you want to use this costume for a "Cabbage Patch Kid" costume, then this is acceptable. Simply wear a bonnet and apply doll-like make-up to make your child appear more like a "Cabbage Patch Kid."