If you go to your local garden center, they sell a product called Liquid Fence. Its a liquid you spray the perimeter of your garden with and it will keep all kinds of rodents along with deer away from your garden. And it only needs to be applied once every 6 weeks. I had a real problem with rabbits and this worked for me. Another solution I've heard, but I don't know if it works is to sprinkle pepper through out your garden, apparently most animals don't like the smell.