Well dogs and lawns don't mix very well if you let the dogs run on the lawn unsupervised. If your dogs are free to do what they want in your yard during the day, you'll never have a great lawn. It's really a choice you need to make. If you really want both, you'll have to consider putting your dogs in a kennel in the backyard while you aren't around. Plus, dogs dig often because they are bored. A well exercised dog doesn't really dig that much so I recommend a 45 minute walk with your dog every day. There are spray repellents you can buy at most home centers or garden shops, but their effectiveness depends entirely on the dog. Unlike cat repellents, which will keep most cats at bay, dog repellents vary tremendously by the nature of the dog. Some dogs will hate a particular repellent, while others will try to eat it. You'll just have to experiment. But, keep in mind, that if your dogs run free in the backyard and have nothing else to do, they will tear up the lawn for something to do. Plus, they'll eliminate on the lawn which will leave spots, etc. I love dogs, I have 6 of them, but I would not expect to have a perfect lawn with them. It's a matter of balance. You can't have a perfect lawn and a dog that's allowed to wander or play on it.