This protective layer of material will go a long way to reducing one of the major causes of water waste - evaporation from the soil surface. The benefits of mulching go beyond water conservation as well. Weed growth will be much less of a problem. Mulches help keep the soil well aerated by shielding the soil from compaction by rain. And plants are better protected from extremes in soil temperature.
Choices There are a variety of materials which make excellent mulches.
Your choice will depend on the look you want and whether your soil needs improving. Organic mulches will decompose over time. Organic mulches include wood chips, partially decomposed compost, bark, and cocoa hulls. Some of these materials, such as bark mulch, will blend in visually with your landscape, while others, like cocoa hulls, provide a good color contrast to plants. As mulches decompose, additional material will have to be spread perhaps once each year so as to maintain a three inch depth.