How do we housetrain our dog who won't go in our yard?

Until you're confident that your pup is able to hold his potty inside, I found the most successful method to be crate training. While it may seem a little sad and lonely in the beginning, it's a great tool to communicate with your pup to hold his bladder. Then, once uncrated, bring him outside to the yard and watch him until he potties. When he does, give him tons of positive feedback and a treat. Soon, your dog will catch on that he gets treats/praise when he goes outsides, and the crate will teach him to hold it. Once you're confident in your dog's ability to hold his bladder, you can ween him off the crate.

It's also important to point out that the crate should never be seen as a punishment. Instead, it should have a positive association with your pup. A den to relax in, chew toys, and get treats!

I found this video to be helpful: