What Does Mulch Do?

Bed of brown mulch with garden tools, flower, and potted plants at right.

Last Updated May 18, 2023

Few materials are as beneficial for your garden or as misunderstood as mulch, and although it is widely recognized as a valuable addition to any landscape, not everyone knows why. The team of professionals at The Grounds Guys® is pleased to provide you with the answers to questions such as "What does mulch do?" and "What is mulch used for?" so that you can reap the benefits and have the garden you've always dreamed of.

What Is Mulch?

Mulch is defined as any organic or inorganic material that is placed atop soil in a garden bed or used in landscape design. While there are a number of different types and varieties of mulch to choose from no one variety can do it all, so it's important to choose a material that will suit your exact needs based on location, plant type, soil, and more. Options include organic and inorganic mulch.

Types of Organic Mulch

Because organic mulches are made from natural materials they decompose over time, adding valuable nutrients to the soil.


Bark mulch.

Wood chips are ideal for use in perennial beds or around trees or shrubs and can be a decorative addition to any landscape. Pine is slightly more acidic than other varieties making it a strategic addition for plants that require a more acidic environment.


Landscaper holding compost for mulch.

Nutrition-dense compost can be used as a standalone mulch or as a healthy boost to plants, providing a continuous supply of nitrogen and carbon. Because it decomposes quickly you can expect to add additional layers of this material each month during peak growing season.

Lawn Clippings

Landscaper holding grass clippings and leaves for mulch.

While they can be an effective weed suppressant, grass clippings should be used sparingly as they can emit an unpleasant odor, prevent the transmission of water, or mat if the layer is too thick.

Shredded Leaves

Shredded leaves for mulch.

Leaf mulch is attractive to earthworms and is a great way to dispose of the leaves on your property. Because it is a less attractive alternative you may want to reserve this mulch for less formal areas of the garden.


Straw mulch.

A layer of straw can help to retain moisture, inhibit weed growth, attract insects, and deter birds and rodents. It decomposes quite slowly and can last through the growing season.

Types of Inorganic Mulch

Inorganic mulch is a long-lasting alternative that can inhibit the growth of weeds, although it provides no nutritive value to plants or soil.

Landscape Fabric

Landscape fabric laid in a garden bed.

In areas of inactivity or where the soil doesn't require fertilization, landscape fabric provides a beneficial barrier against weeds, though it can also prevent the passage of water and vital nutrients.


Stone mulch.

Ideal for areas that require assistance with drainage or heat retention.

Benefits of Mulch

In addition to enhancing the appearance of your landscape, mulch has a number of other benefits including:

  • Moisture retention
  • Weed control
  • Prevention of soil erosion
  • Maintain or add to the nutrition of the soil
  • Pest control
  • Attracts earthworms
  • Cedar, cypress, and pine wood can help to repel fleas, ticks, and gnats

Maintenance and Tips for Mulch

Apply the mulch in layers between one and three inches thick to encourage oxygen flow and prevent rot.

Leave space between the base of trees or plants to prevent disease or rot. Wood or bark mulch should be watered thoroughly upon installation.

Consider adding a source of nitrogen to the soil before applying wood mulch, as stores may be depleted during the decomposition process.

Need Assistance with Your Next Landscaping Project?

The Grounds Guys offer a wide range of residential and commercial landscaping services, including mulching. Contact The Grounds Guys to learn more, or to request a free estimate today!