Mulch: A cover to protect plant roots.
The use of mulch will improve water infiltration and reduce storm water runoff. An additional benefit is that mulch will shade the soil reducing water evaporation. Choosing to use an organic mulch will improve the soil texture over time. Also, it can suppress weeds that compete with the desired plant. How well a mulch conserves moisture is determined by its composition and how it is applied.
Listed here are several of the most commonly used landscape mulches available. Deciding which mulch to use will depend on its cost, availability, ease of use, durability, and its appearance in your particular situation.
Plastic or Polyethylene Film - available in clear or black and with or without perforations
Advantages: Prevents moisture evaporation effectively, thin, lightweight, inexpensive, though perforated plastic is more expensive.
Disadvantages: Can cause roots to concentrate at soil surface increasing drought susceptibility, doesn’t improve soil structure, needs shade to reduce summer heat buildup.
Landscape Fabric - Geotextiles, ex. “Weed Barrier,” “Weed-X,” “Weed Block”
Advantages: Water permeable, suppresses most water competing weeds, durable.
Disadvantages: Expense, allows some weeds to grow, needs to be secured to keep in place.
Wood or Bark Material - wood chips, tree trimmings, shredded or bark chips,
Advantages: Inexpensive to relatively expensive, lets in water and retains it in soil, breaks down to improve soil texture, smaller sizes suppress weeds better.
Disadvantages: Breaks down in one to three years depending on particle size and type of tree used, can blow or wash off of desired location.
Stone or Gravel
Advantages: Allows moisture in and retains it in the soil, long lasting, variety of sizes, can have ornamental appeal, suppresses weeds.
Disadvantages: Increases temperature around plants in summer, tends to get scattered, price varies, doesn’t improve soil.
Fine textured mulch is applied at a shallower depth than coarser materials. For example, maintaining an inch of sawdust or grass clippings will be sufficient for water and air movement in the soil. Coarse wood chips and river rock can be applied at a 2 to 3 inch depth to allow water and air movement and reduce weeds and evaporation.
Mulch should be 2- to 3-inches thick for best results.
There are many different textures/colors of mulch.
Vegetables also benefit from mulch.
Use a wheelbarrow and a friend to easily move mulch purchased in bulk.
Another good reason to mulch around the base of trees – to keep weed trimmers away.