Natural mulches are materials such as straw, hay, compost, composted bark, or pine needles.
Synthetic mulches are plastics and papers. Composted sawdust, bark, wood shavings, leaves, grass clippings, rice hulls, ground corncobs, and animal manures may also be used. Plastic mulches are springtime mulches. Newspaper is an organic material, but as a manufactured product it may be thought of differently from other organic mulches. Newspaper makes a good mulch when you use a thickness of several sheets.