I use hay that is often waste hay of the ranch. I run it through the chickens, and they clean up any weed seed (the theory) and then use it in the garden as mulch. I do keep a pitch fork in the run, and rake it up into piles, mini hay stacks, before snow, then flip it on top of the snow. It also allows the ground to dry out in places. The girls and I stir up pretty frequently, makes a better garden.