Only thing I can think of is to put something near that would "appeal" to them, laced with say, cayenne pepper inside of it. That way you can build up a food adversion to it, much like people do when they get sick from a certain food. For example, I hate jelly beans but that's only because I went on a field trip to a jelly belly factory when I was in elementary school. After a few minutes of trying them, I threw up. In all likelyhood, it was probably the motion sickness from the bus, coupled with an empty stomach that caused me to throw up. But because of that episode, I refuse to eat anything resembling a jelly bean. I would imagine it would be the same thing for whatever is having it's way with your garden. Place enough things around there for it to eat but lace them with something that would cause them to think twice about eating from your garden.