I read up on this a few years ago and decided to make my own and seeing as there are no instructables on it I had to make one!
I have a really big gopher issue and them eating my tree roots and any flowers or vegetables I plant. this set up doesn't "eliminate" the pests but it doesn't feed the. now either. Also it will be easier to maintain as there are little to no weeds to pull and sitting on your knees to plant, fertilize, and harvest is nice since everything is at chest level and you don't have to bend over. plus you can sit on them and work if you like too!