We built "vegetable alcatraz" 10 years ago. I have yet to see one of our countless fluffy cotton tails or jack rabbits in there. We used railroad ties and masonry blocks to outline the garden. Then added 3 foot chicken wire as fencing around that. On the outside of that we put a 1 foot tall continuing band of aluminum (or other slick metal) sheet at ground level to keep mice, rats and squirels from climbing in. Then we hung some black netting over the whole thing. Sounds like a lot of work but we never lost anything to critters
