Mulching is an easy-to-do labor-saving gardening technique that all gardeners should take advantage of. A mulch is a material, usually organic but sometimes inorganic, that we use to cover the soil surface around plants. Mulching beds is an important part of sustainable landscaping.
Organic mulches, such as leaves, chopped leaves, pine straw, ground pine bark, dry grass clippings and newspaper, are all derived from once-living materials. They are popular for their ease of use, attractive appearance (except for newspaper) and because, as they decompose, they add beneficial organic matter to the soil. They are the most popular mulches.
Inorganic mulches are derived from nonliving sources and include such materials as plastic sheeting, landscape fabric or weed barriers, stone chips or gravel. Rubber mulch made from recycled tires and synthetic pine straw are inorganic mulches that have the look of organic mulches but last longer.
The first and foremost reason to use mulches is to control weeds. Every time weeds are removed, new weed seeds germinate, creating the problem all over again. Mulches work to stop this by blocking light from reaching the soil surface. Most weed seeds need light to germinate as this tells them they are close enough to the soil surface to sprout and grow. When covered over with mulch, they think they’re still deep in the soil and will not germinate.
To create this barrier to weed growth, organic mulches have to be applied thick enough to do the job. Apply organic mulches about 2 inches thick around bedding plants and vegetables and 2 to 4 inches thick around shrubs for best weed control.
Another important function of mulches is conserving moisture in the soil. Your plants receive a more even supply of moisture and you save money on your water bill. Mulches also moderate soil temperature and reduce soil compaction. That’s a lot of benefit from a simple gardening technique that is easy to do.
Which mulch you choose depends on a variety of factors, including the gardening situation, your preference based on appearance, what’s available, cost and durability. I like to recycle yard waste such as leaves, pine straw and dry grass clippings and use them.
If you currently are not using mulches in your gardening efforts, I strongly recommend you give them a try. You’ll be amazed at how much work they save you weeding and how nice they can make a garden look. If you are mulching, remember their primary function is not just decorative, so apply mulches thick enough and throughout your landscape beds and gardens.
The LSU AgCenter and the LSU College of Agriculture