If you can get your hands on a plant called Coleus Canina (hybrid) it is supposed to keep cats and dogs from fouling your vegetable and flower beds. I gives off an aroma which they hate.
By gardenfairy from Ireland
What is the best way to keep pets away from sown areas?
By anura from New Zealand
I read a tip here that I am going to try and that is using vinegar on paper or on rags; need to be sure and keep wetting it but the smell is said to keep all critters away! Hopefully this will work for me as well! Good luck!