My girls are out in a travel cage most days, 10-14 hours a day, weather permitting on our grass. The grass looks like it is dying for about 2 weeks before bouncing back looking much healthier than the areas they haven't been in. As I don't care for lawns (wasted space for the most part IMHO, but it's a rental house), I don't do anything beside mowing. They fertilize the areas where the cage has been effectively.