Any gardener will tell you that mulching is an essential element of landscaping. However, there is more to mulching than just spreading some straw or peat moss around your trees, shrubs and flowers. Mulch should, at the very least, have these qualities: insulate plants & roots, increase water retention, be attractive, have a pleasant odor or be odor free, allow water and air to penetrate soil and it must stay in place. Although there may not be an ideal or perfect mulch, several come close. Finding the right mulch for your purposes just takes a little research and maybe a few trips to the home improvement store or local garden supply store.
Before deciding what material to use as mulch, you need to decide between organic mulch and inorganic mulch for your landscaping. Both inorganic and organic mulch have certain characteristics that make each ideal for certain types of mulching projects. For example, organic mulches are eco-friendly and provide a continuous source of organic matter to the surface of the soil. However, if organic mulches are kept too wet they can breed mold. Hay, straw and other organic mulches may contain weed seeds that will be introduced to your yard and garden through the mulch. The merits of organic mulch probably outweigh the problems though. For instance, organic mulches alter the soil providing aeration in soil heavy with clay and more moisture retention in sandy soils. Inorganic mulch also has its own unique characteristics that make it both ideal at times and a detriment at other times. Inorganic mulch lasts much longer than organic mulch because the materials do not decay like the materials in organic mulch. Furthermore, most inorganic mulches prevent weeds or even completely inhibit weed growth. However, inorganic mulches are difficult to remove once they are in place, can prevent moisture and air from circulating through the soil and do nothing to improve or add nutrients to the soil.
Knowing when to mulch is also a key element to proper mulching. There are two seasons for mulching: growing season and dormant season. Mulching during growing season helps to maintain moisture until the new plants have become fully established. Furthermore, mulching during growing season reduces loss of soil and soil erosion until turf or plants are established. Mulch should not be applied until the soil has warmed up to promote active root growth – – if not, the mulch will keep the ground cool and roots will not grow. Dormant season mulching protects plants and roots from severe temperature changes by maintaining a constant soil temperature. However, dormant season mulching should not be done too early in the season or it will prevent plants from developing key processes that help them survive cold weather. Furthermore, pruning, fertilizing or doing anything to stimulate plant growth should be avoided after dormant season mulching has been done.
Some general precautions when using mulch include:
**Do not use reflective mulch (white rock, shiny pebbles, etc.) at the base of a building or home. They reflect the summer heat toward the house as well as damage plant roots by causing too much warmth during dormant winter months.
**It is not wise to use wood mulch around homes because this type of mulch attracts termites and other insects that will enter your home through cracks and spaces in the foundation and walls.
**Using mulch on soil that is poorly drained (soil that retains moisture and water) can cause the soil to be too wet for plants.
**Leaves, sawdust and shredded bark (all organic mulch) should be moist when they are applied to lawns and gardens. If they are dry, they will soak up the moisture from the soil leaving plants without water.
University of Rhode Island GreenShare
Williams, David J. “Organic Mulch) (University of Illinois at Urbana-Champaign, NRES-19-97)