I would say, depending on the breed and the dogs' individual personalities, you might be able just to train them to avoid the beds. OTOH, there are dogs that I consider to be hopeless cases in such situations ... such as the 2 I own.
My Lab mix just galumps along and mows down anything in his path, and the little dog (allegedly a Blue heeler/Dalmatian mix) can't seem to tolerate the sight of a piece of ground that doesn't have craters dug in it. :p I have a hard time keeping her from digging in my planter boxes on the patio, and they aren't that big. I dread the thought of the destruction she'd wreak if I were to try to put a garden bed in the back yard!
That's the reason I garden in containers on the south side of my house. Years ago, I installed a chain-link fence, separating that area from the back yard. That means the dogs can't get at my plants. Originally, the area was used as a dog run, when I had Komondorok that I showed. To that end, I had the area dug out and filled with 18" of sand topped with gravel for good drainage, so I can't just plant in the ground, but the containers work just fine.