In the high plains grasslands, dead grass and plants accumulate. These plant remains are natural mulches and are a great benefit for growing plants. They keep the soil moist and loose, permit air and water to pass freely to plant roots, and reduce soil erosion and weeds. Following Mother Nature's example will provide those same benefits in a yard. A layer of mulch on a xeriscape keeps soil cooler and reduces evaporation so less water is needed.
Mulches can also reduce weeds and can add color and texture to a landscape.
In Colorado, the most common organic mulches include wood chips, chunk bark, pole peelings, pine needles, lawn clippings and straw. Organic mulches gradually break down and add nutrients to the soil. They will need to be renewed periodically. Decomposition of fresh wood mulches can create nitrogen deficiencies. Be prepared to supplement the area with a fertilizer.