This year in the bay area we are on water rationing. I've been covering every bare place in my yard with anything that I could scrounge of plant matter. I've cut back my tall growing irises after they bloomed to use the stems, used the neighbor's cut grass, pulled up any excess of plants that had overgrown their area, added weeds that I pulled up or raked, put down newspaper under them to increase the effect. Since our city has "green bins" for people to put their plant refuse in to recycle into city mulch, my chance at using the neighbor's plant debris has been reduced.