OK, I would recommend that you buy hardware cloth of the 3 foot dimension... No sense burying it inside the coop... Place it up the outside wall a minimum of 8 inches and make SURE it is FIRMLY attached (I would staple or screw with washers then place a trim board over that and nail/screw it at close and regular intervals). then run the remaining 2 feet out along the ground away from the coop and bury under a few inches of dirt. Any predator wanting to dig under the coop will start right at the coop edge, not 2 feet out from it. You have to make sure it is firmly attached so they can't pull it away from the coop where it's attached, and then go under it. You can plant grass over it and mow as normal, or whatever you'd like... maybe decorative gravel? Didn't you say you had very rocky soil?