Control weed growth. Keep soil temperature uniform. Reduce frost damage to fruit. One of the most effective ways of reducing the need to apply water to garden plants and conserve natural rainfall is to use garden mulches. Mulches are most appropriately used on summer crops when periods of water use are greatest.
Mulches provide a barrier that helps prevent moisture loss from the soil by evaporation.
They also can be useful in maintaining cooler soil temperatures, controlling weeds, reducing soil compaction, and keeping produce cleaner. Plastic mulches Black polyethylene mulch is preferred because clear plastic mulch promotes weed growth underneath it. Plastics usually are available in rolls from 3-4 feet wide. They are placed over the row or bed, the edges covered with soil, and various sized holes cut for the different crops. Black surfaces absorb heat, warming the soil for earlier production.