In the past we have had a problem with the neighborhood cats(and our own) using our garden as a liter box. Yuck! So to stop them in their tracks, so to speak ,we devised a way to stop them from digging. This method is completely harmless to the cats and other creatures.
We went to our local home improvement store and bought a large roll of plastic bird mesh. We layed it over every square inch of our garden.We also made sure that the edges were weighted down so that the more clever of the pets wouldn't be able to move it aside. As the seedlings come up, we cut small slits down the rows.
The kitties cannot dig and do not like the feel of it on their paws.
By Angi from Spokane, WA