Is Mulch a Natural Weed Barrier?

How Mulch Helps to Control Weeds

• Weed seeds have the same germination requirements as those of other plants: water, oxygen, the right temperature and sunlight. An adequate layer of mulch creates a barrier between the germinating seed and the sunlight, allowing only the strongest and largest weeds to make it through. Mulch also helps to keep the soil cooler, delaying or inhibiting the germination of weed seeds.

How to Apply Mulch to Your Landscape

• The proper application of mulch in your landscape will determine the effectiveness of your weed control. The thickness of mulch is the most important factor in controlling weeds. Too little mulch will not provide adequate control, while a layer that is too thick could be harmful to the plants you want to keep and is wasteful. In general, a layer of 2 to 3 inches is optimal and will achieve the best results.

  Applying mulch is easy, but labor intensive. Make sure to do all of your bed preparation in advance of putting down your mulch. Once your flower bed is level and all your flowers planted, then you can mulch. A wheelbarrow and garden rake are necessary equipment for this step. Once you have transported your mulch where you need it, dump it out in several piles and spread it out evenly across the soil. Don't pile mulch around plants or tree trunks as this can be harmful to their growth.

What Types of Mulch to Use

• The most common types of mulch are natural materials like shredded bark, chipped wood, pine straw, grass clippings, barley straw or cocoa bean hulls. Although the term mulch is often associated with natural products, inorganic material, like gravel or tumbled glass, also work well as mulch. Natural mulches have an additional benefit of adding organic matter to your soil, but unlike inorganic mulches, they need to be replenished annually.

  Other common mulches used for weed control are cardboard or newsprint. When applied in layers, these materials will control weeds and add to the organic content of your soil.

How Well Mulch Controls Weeds

• Any successful weed control program will incorporate several different methods of control to achieve satisfactory results. Correctly applied mulch will help to control weeds, but will not prevent all weeds. Make sure to incorporate other weed control methods such as herbicides or manual removal to get the upper hand on weeds in your yard.