Advice for doggies

Sarah • 22

So i rent a house and it has a big back yard. The problem is it’s all dirt! We have asked the land lord if we can plant grass, and he won’t let us. My dog is filthy and i wish she had something other than dirt to lay on because she likes to sunbathe. I was thinking of getting some fake grass but I’m not sure how that would hold up, it will probably just get covered in dirt too. Does anyone have any suggestions??