There are many benefits to using organic mulch. The first, and most important, is that it contains zero chemicals. They typically consist of shredded trees, plant trimmings and other organic plant material, sometimes even locally. Mulch of this kind helps to prevent evaporation of moisture in the soil allowing for less frequent watering. Also, because this mulch is organic, it absorbs water and makes it less likely to wash away. Hardwood mulch naturally contains nutrients beneficial to roots as well as micro-organisms that assist in breaking down the decaying wood matter. This process will not only turn the mulch into composted topsoil over time, it also creates an increase in Nitrogen in the soil which is a vital element to plant health and growth. Hardwood mulch does breakdown slowly, but will still need to be refreshed at least once a year with a new application of fresh material.