Right now my chickens are only 4-6 weeks old. I open up the coop to the yard every morning and close them up at night. I have a large number but I am planning to downsize to the ones I really like as they get bigger. My full-grown chickens free-range about 5 days per week When the little ones get to be 3-4 months I will start letting them out into the yard. We have a 3-acre "yard" and 14 acres of pasture surrounding. We usually have around a dozen cattle in the pasture in the summer to keep the grass from taking over so we can keep a pretty good eye on things. Our dog is good at watching over the chickens, too. So far his German Shepherd side is making him a good guardian, but then I think his Lab side has come to an understanding with our rooster. Maybe he just decided wild rabbits are more fun, lol!