natural dog repellent

Long story short, my puppy (old english sheepdog) takes pride in digging up our turf. mainly along the fencelines. I dont share the same appreciation as he does, and need to know if there are any good recipies for dog repellents that i can spray along the fence without hurting the grass or my stubborn dog. I tried pepper, but he seems to enjoy the taste more than it repells him.

Please, serious responds only.

Thanks

natural dog repellent