I've heard that it is good for their stomachs? If that's right, then I have an idea, but feel free to tell me if it is a bit silly 
Our garden (the part that the dog has unsupervised access to occasionally) is patioed over with a raised flower bed running along the length of it. As it is coming to summer time and I will probably be at home for the six week holiday, I'm hoping the weather will be good enough to have the door open all the time so he can come and go as she pleases - and it would be nice if I could be out with her 
Because of her personality, she just enjoy running when we are out on her walks, so I'm contemplating playing grass seed in one area of the raised bed so there is grass for her to eat. Is that a silly idea?