Mulch protects the soil, prevents weeds, and provides nutrients to make rich, loamy topsoil. It keeps too much water out, and enough water in.
- When to mulch: In the spring and fall (after the ground is frozen for those in the North).
- How to mulch: Cover all exposed soil with 2 inches of mulch. This will help prevent runoff during heavy rains.
- What to mulch with: Nutritious mulch includes dried manure (age six months before spreading), wood chips (contact your town road crews for a possible source), corncobs, leaves (just make sure they are torn up leaves so they don’t mat), grass clippings (from unsprayed lawns), pine needles, hay, stones (they retain heat—helpful in northern climates—and protect the soil from torrential rains), straw, seaweed, peat moss, sawdust, and many other natural, organic materials. Black plastic spread over the soil is used to eliminate weeds and retain the moisture of the soil, but won’t impart any nutrition to the soil.
- Is green manure a mulch? Green manure is not actually a mulch, but crops that are planted in soil to protect the soil from runoff and to provide the soil with nutrients. Traditional green manure crops include clover, winter rye, or alfalfa. The crop is turned into the ground the season after it is planted. A great USDA-devised mulch system for tomatoes uses the green manure groundcover hairy vetch.