What is Mulch?

What is mulch? Mulch is any material like leaves, wood chips, bark, rubber, fabric, or grass clippings used to reduce erosion, prevent weeds, keep soil temperatures level, and increase your home’s curb appeal. 

Learn more about the different types of mulch you can use in your yard, where to use it, when to apply it, the benefits, and how to apply it.

Types of mulch

Made from organic or inorganic materials like wood chips, leaves, straw, rubber, fabric, or a blend of these, mulch forms a protective barrier for your soil. It promotes plant health and defends soil in gardens, lawns, or landscapes.

Whether you want to spruce up your curb appeal or enhance soil health and plant vitality in your garden, mulch can help with all of that and more.

Organic mulch

Organic mulch is made of plant-based materials that decompose over time and provide the soil with organic matter and nutrients. It’s biodegradable and environmentally friendly, contributing to soil health and biodiversity. 

Here are some common organic mulches you can use in your yard:

Shredded bark

As the name suggests, this mulch is made from shredded tree bark, popular for its attractive appearance and ability to retain moisture. It decomposes slowly, enhancing soil quality and providing long-lasting weed control. 

Where to find it: Local garden centers and nurseries often carry various types of shredded bark. They may offer bulk delivery or allow you to purchase bags of mulch for smaller projects. 

Where to use it: Use shredded bark mulch to cover the soil surface around trees, shrubs, flowers, and other plants in garden beds. You also can apply shredded bark mulch along walkways, driveways, or property lines and create natural-looking pathways in your garden or backyard.

Wood chips 

A versatile mulch made from chipped or shredded twigs or branches, wood chips come in different sizes and textures helpful in the garden. 

Where to get them: Many cities or municipalities offer wood chipping services as part of their yard waste recycling programs. Get in touch with them and you may be able to get wood chips for free or at a nominal cost. Likewise, tree service companies or arborists produce wood chips as a byproduct of tree trimming or removal jobs. Last, think of landscaping supply stores or home improvement stores.

Where to use them: Wood chips are commonly used as mulch in garden beds, around trees, shrubs, and flower beds. Aside from that, they can serve as soil amendment, decorative landscaping, or cushioning material in playgrounds.

Leaves

If leaves are plentiful in your yard, use them as mulch shredded or whole (after all, they’re free). Freshly fallen leaves can bring a colorful and vibrant appearance to the yard, especially in the fall and in combination with other mulching materials such as wood chips, bark, or stones.

That said, decomposition can leave them looking brown and unappealing, which is why some gardeners prefer other mulching options. 

Where to get them: Your options are endless. Get leaves in your own yard, from neighbors or the community, local municipal leaf collection agencies, or landscaping companies. You could try your luck with community gardens and farms; some accept leaf donations that can be shared with you.

Where to use them: Spread a layer of shredded leaves over garden beds to improve soil health. Alternatively, you can apply them around trees and shrubs, in vegetable gardens, around perennials and annuals, or along pathways and walkways. Don’t forget they can be composted as a “brown” material to balance out “green” nitrogen-rich materials.

Compost

Compost is a blend of organic matter, such as kitchen scraps, yard waste, and plant materials.  The good news? You can easily make it yourself.

Where to get it: As already mentioned, you can make use of scraps in your own household for mixing compost. Secondly, look to municipal composting agencies, garden centers, farmers’ markets, or online retailers for help in getting compost. 

Where to use it: Use compost to topdress lawns or container gardens or provide essential nutrients to trees and shrubs. Keep the compost mulch several inches away from the tree trunks or shrubs to prevent pest attacks and moisture-related problems.

Straw

Straw mulch is derived from dried straw or hay and is commonly used in vegetable gardens and agricultural settings. It decomposes slowly and won’t require re-application throughout the growing season. Some cool uses for straw include making animal bedding for chickens, rabbits, or horses, creating straw bale garden beds, and using it for Halloween decorations, wreaths, ornaments, baskets, or other seasonal decorations.

Where to get it: Try your luck with feed stores, online retailers, agricultural supply stores, garden centers, and nurseries.

Where to use it: You can place straw around perennials and annuals, potatoes, and the base of fruit trees.

Cocoa bean hulls

These are a byproduct of cocoa bean processing. They decompose slowly and boast a pleasant aroma. Talk about slow-release fertilizer for your garden. Their rich, dark brown color can look beautiful when spread around plants, giving off a polished look that’s sure to impress.

Where to get it: You can often find cocoa bean hulls at specialty landscaping stores that carry them in bulk. Similarly, look for them at garden centers, nurseries, or cocoa processing factories that may sell them to the public.

Where to use it: Use them in your annual garden or areas vulnerable to weeds due to high traffic. In the same vein, decorate flower beds and borders or create natural-looking pathways in your yard.

Grass clippings

You may have heard that grass clippings contribute to thatch buildup, but that’s just not the case. Thatch is only caused by living and dead roots, shoots, and stems that accumulate on the soil surface. Lawn clippings, on the other hand, quickly break down and feed your soil. So before you bag those clippings, why not give mulching a try instead?

If you use herbicides, pesticides, or synthetic fertilizers on your lawn, don’t use grass clippings as mulch. Chemical residues from these products can remain in the clippings and may harm beneficial organisms in the soil or affect the health of your plants.

Where to get them: After mowing your lawn, rake up the clippings and use them. Alternatively, look to local lawn care companies, or ask your neighbors for some extra clippings. Many people are happy to give away their clippings to avoid the hassle of disposal.

Where to use them: Add grass clippings to compost or sprinkle them over a newly overseeded lawn to protect the seeds from birds and pests. You can also place them in vegetable gardens or at the base of trees or shrubs. If you want to feed your lawn, mow it and leave the grass clippings on the lawn as fertilizer.

Pine needles

If you’re growing blueberries, azaleas, rhododendrons, or other plants that like acidic soil, pine needles (or pine straw) can maintain these conditions and help them thrive. In addition to being fluffy to work with, pine needles provide that rustic, natural appeal thanks to their earthy tones and textured look. Another great thing about pine needles? They decompose slowly, so they last much longer than grass clippings, for example.

Where to get them: If you live in an area with pine forests or wooded areas, you may be able to collect pine needles directly from the ground. Don’t forget to get permission if you’re collecting them from private property or protected areas. Also, try looking for them at local pine straw suppliers, landscaping stores, or garden centers.

Where to use them: Use them around acid-loving plants and flowers, in vegetable gardens, or in container gardens. Keep them away from fire-prone areas, as they catch fire quickly.

Aged sawdust

Aged sawdust is an affordable mulch that can suppress weeds and conserve moisture in spring when plants and grass come out of dormancy. It’s particularly useful for acid-loving plants such as azaleas, rhododendrons, daffodils, hydrangeas, and blueberries.

Using sawdust on plants has raised the question of whether the resin present in the sawdust can injure plants, but according to Wesley P. Judkins of the Virginia Polytechnic Institute, there is no conclusive evidence that such injury can occur.

That said, sawdust should be aged for a minimum of several months to allow it to decompose and stabilize before using it as mulch. The microbial activity during this time helps break down the carbon compounds and reduce the risk of nitrogen deficiency.

Where to get it: Sawdust is a byproduct of lumber processing, which means you can typically get it at sawmills. The same goes for tree companies or arborists. If that doesn’t work, try agricultural supply stores, local farms, or online retailers.

Where to use it: Sawdust is handy for composting, in garden beds, or around trees, shrubs, and rose or berry bushes. Don’t pile it on too thick around tree trunks as it can cause rot.

Groundcovers

Want a mulch that also serves as an appealing lawn? Try planting ground cover. It will save you the hassle of spreading mulch and boost your curb appeal. Select low-growing, spreading plants to cover bare soil, such as creeping thyme, creeping Jenny, ajuga, or sedum. These plants provide a living, decorative cover your neighbors will go green over.

Where to get them: Groundcovers can be purchased at local nurseries or garden centers. If your local community offers one, try a seed exchange. Alternatively, look for inspiration online.

Where to use them: Most people use groundcovers on slopes and banks to stabilize and prevent erosion. Alternatively, try using them as a gap-fill between pavers or around ponds, fountains, and other landscape features.

Inorganic mulch

Inorganic mulch comprises materials that don’t decompose, such as rocks or landscape fabric.

Since inorganic mulch doesn’t decompose, it isn’t helpful in lawns. It’s mostly beneficial in decorative situations like flower beds where you want to prevent weeds or areas where you want to control growth (such as around an ornamental plant). It also can look nice lining your lawn, contrasting it with the surrounding landscaping.

Some excellent inorganic mulch options for your yard include:

Gravel

Gravel is a popular inorganic mulch made of small stones or pebbles. It comes in different shapes, sizes, and colors, allowing you to customize it to fit your yard’s vibe. 

Where to get it: Of course, gravel is available at home improvement stores and online. But, if that’s not an option, you could try stone suppliers or quarries. They normally sell gravel in bulk for landscaping projects.

Where to use it: Most homeowners use gravel for xeriscaping and drought-tolerant landscaping. This option is useful if water conservation is a concern. You also can use it in your driveway, underneath your porch or deck to create a crisp, clean look, or as decorative material in your container garden.

River rock

Think of river rock as nature’s gift to landscaping. This type of mulch consists of smooth, rounded stones found along a riverbed. It offers similar benefits to gravel mulch, including weed control and moisture retention, and adds a touch of rustic charm to garden beds and pathways.

Where to get it: Like gravel, river rock can be obtained from quarries, stone suppliers, or home improvement stores. These stores typically carry bags of all sizes, whether you’re tackling a smaller project or going big with your entire yard. If you’re looking for free river rock, you could look at construction sites, talk to a farmer, or go online.

Where to use it: River rocks can be spread along borders or used to create rock gardens. If you’re feeling creative, you could build water features such as ponds or waterfalls or apply them around garden beds for some texture.

Landscape fabric

Landscape fabric is a synthetic material made of woven or non-woven polypropylene that’s placed on the soil surface before planting. 

Once installed, landscape fabric requires minimal maintenance apart from the occasional inspection for signs of sunlight, moisture, or age damage. Once it deteriorates, you’ll need to replace it to continue reaping the benefits it offers.

Where to get it: Home improvement stores, garden centers, nurseries, and landscaping supply stores all carry landscape fabric. Online shopping gives you the advantage of comparing brands and reading customer reviews before purchasing.

Where to use it: Landscape fabric can be used as a barrier underneath organic mulches such as wood chips, bark, or shredded leaves, or other inorganic materials like gravel or river rocks. If you want to use it around a tree trunk, make sure to cut the fabric to accommodate the size of the tree and allow for proper drainage and airflow. When it comes to erosion control, landscape fabric can work wonders by stabilizing the soil.

Rubber

Made from recycled rubber tires, rubber mulch is available in a range of colors and textures to match your landscape. As an excellent impact absorber, rubber provides a soft, safe surface for children and pets to play on. It does not rot, fade, or shrink, making it perfect for high foot traffic areas.

Where to get it: You can purchase rubber mulch at home improvement stores or try online shopping. Alternatively, turn to a local rubber mulch manufacturer for guidance and a wide range of colors and sizes.

Where to use it: Rubber mulch is often used around trees, shrubs, or flower beds, as well as in playgrounds, walkways, and areas where traditional mulches may be impractical. As it doesn’t attract termites, rubber is also typically placed around foundations and buildings, reducing the need for insecticides in the landscape.

Plastic

Often found in agricultural settings, plastic mulch is a thin, flexible material made from sheets of polyethylene or other plastics. While it comes in various colors, black is the predominant choice for weed control.

One drawback is that plastic mulch contributes to surface water runoff, whether from rainfall or irrigation. As such, pesticides or herbicides applied to gardens or fields can more easily pollute bodies of water or the soil. 

Where to get it: Plastic can be found at garden centers, agricultural supply stores, home improvement stores, or nurseries. Whether in sheet or roll form, you’ll find a selection of sizes and colors to suit your needs.

Where to use it: Plastic is often used to regulate soil temperatures, easily absorbing and retaining heat. It’s also an excellent choice for decorative landscaping or for use under gravel or rocks to prevent weeds from pushing through.

Benefits of mulch

Mulch offers so many benefits for your garden and landscaping. Here’s what you can look forward to by adding mulch:

• Healthier soil: Packed with organic matter and nutrients that your plants love, mulch is like a superfood for your soil. Use it to promote microbial activity, which plays a pivotal role in decomposing organic matter, releasing nutrients, and suppressing soil-borne pathogens. 
• Moisture retention: Mulch reduces evaporation, thus enhancing soil moisture retention. If you’re environmentally conscious and looking to conserve water, mulch is a great choice for your yard.
• Level soil temperature: Mulch insulates the soil. It keeps it cool in hot weather and warm in cold weather, providing a stable environment for plant roots.
• Less compaction: Mulch serves as a cushioning layer that reduces soil compaction

caused by heavy rain or foot traffic. Think better root growth and water absorption.

• Visual appeal: Want to boost your landscape’s visual appeal? Use mulch. It provides a neat appearance that contrasts nicely with the plants’ greenery.
• Disease prevention: Did you know that certain types of mulch, like cedar or cypress, contain natural compounds that repel pests and inhibit the growth of fungi and bacteria? 
• Optimal soil pH levels: To grow healthy plants or grass, you have to find that soil pH sweet spot. That’s where mulch comes in. It can help regulate soil pH, gradually making it more acidic or alkaline, depending on your needs.
• Less time and effort spent on yard care: Adding mulch to your landscape cuts down on constant weeding, watering, and fertilizing.
• Fewer overall costs: Sure, mulch has an upfront cost, but overall it will cut down on the cost of your water bills, herbicides, fertilizer, and yard maintenance.

When to apply mulch to your yard

The timing for applying mulch to your yard depends on the type of mulch you’re using, your climate, and the specific needs of your lawn and plants. In general, there are two primary seasons for applying mulch:

• Spring: Mulching in spring helps suppress weeds, improve soil moisture, and regulate soil temperature as the growing season begins. It also can boost curb appeal. Before you start, ensure the soil has thawed and is not excessively wet. Applying mulch too early in spring when the soil is still frozen or waterlogged can cause moisture-retention problems, attract fungal diseases and pests, and contribute to root rot. 
• Fall: This is an excellent time to apply mulch to your grass and plants. Besides protecting the roots during the winter, it retains soil moisture and provides insulation against temperature extremes. Spread the mulch in late fall before the ground freezes, allowing it enough time to establish a protective layer for the winter.

How to apply mulch to your yard

To apply mulch effectively to your yard, follow these steps:

1. Gather your materials

Before you get started, make sure you have the following items available for use:

• The mulch of your choice
• Gardening gloves
• Rake or garden fork
• A wheelbarrow or buckets for transporting mulch
  

2. Calculate the amount of mulch you need to apply

To calculate how much mulch you need in cubic yards, use this formula:

• Length x width x depth (in inches) / 324 = cubic yards needed

*Note: 1 cubic yard of mulch covers 324 square feet at 1 inch deep.

For example, if you’re mulching a 10-by-10-foot area that is 3 inches deep, you would need approximately 1 cubic yard of mulch:

• 10 x 10 x 3 = 300/324 = 0.93 cubic yards

For round areas, use the following formula:

• π (3.14) x radius (in feet) squared x depth (in inches) / 324 = cubic yards needed

*Note:

• The radius is determined by measuring from the circle’s center to the edge.
• Radius squared is simply the radius multiplied by itself.

For example, if the radius is 5 feet and you’re applying a 3-inch layer of mulch, you would need approximately 1 cubic yard:

• 3.14 x 5 x 5 x 3 = 235.5/324= 0.72 cubic yards

For irregular shapes, you can break the area into smaller, more manageable sections. Use the formula for rectangles or circles to determine the amount of mulch needed for each section. Then, add all the sections together to get the total amount of mulch required for the entire area.

A general rule of thumb is to apply a layer of mulch 2 to 4 inches deep.

3. Prepare the area you want to mulch

Remove debris, weeds, and rocks before applying mulch to create a more hospitable environment for it. Aerate the soil to enhance the effectiveness of mulch and allow its nutrients to penetrate it better.

4. Choose your mulch type

Whether you choose organic or inorganic mulch, make sure it works best for your yard. Organic mulches are slow-release and truly impact soil health. They create a natural, earthy look and boost fertility. On the other hand, inorganic mulches offer that clean look, don’t decompose, and require minimal maintenance. 

Mulch type also matters when it comes to location, which is why we’ve provided some guidelines:

• You’ll want to choose shredded bark or wood chips for a more natural look to your flower beds. In more visible areas, you can go for colored wood chips or decorative stones.
• When it comes to weed control and moisture retention in vegetable gardens or around flower beds, think about adding shredded leaves, compost, or straw, all of which can help you achieve those goals.
• In a sloped area prone to erosion, choose a mulch type that can prevent runoff due to its ability to anchor itself. Again, shredded bark or wood chips can help since they won’t wash away as easily as finer mulches such as straw or compost.

Bottom line: Let your budget, maintenance capabilities, and gardening goals guide you when selecting mulch.

5. Apply the mulch

Using a rake or similar tool, spread a thin layer of mulch in your desired location (this can be around the base of trees or shrubs, in your vegetable garden, or around plants in flower beds). Try not to pile it right against the plants or trees, as this can contribute to disease and rot.

If you have a large yard, work in sections. Start at one end and work your way across the target area slowly. Make sure not to exceed a mulch depth of 2 to 4 inches, as you can suffocate the plant roots and prevent water absorption.

Once you’re finished, use your hands or the back of the rake to smooth out any uneven surfaces.

6. Reapply as needed

Organic mulch breaks down over time, so monitor the thickness of the mulch layer and reapply as necessary. One thing to remember: Too much mulch could smother your grass and prevent air, water, and nutrients from reaching the soil, so don’t overapply.

7. Water after applying mulch

If applying organic mulch, water it with 1 inch of water to help it settle and start the decomposition process. This also aids in nutrient release and improves soil moisture retention. Check the soil periodically and make sure it stays damp, not wet. If it feels dry to the touch, it’s time to water.

8. Turn mulch piles regularly

This process helps the organic matter decompose evenly and receive proper airflow, prevents compaction, weeds, and diseases, and keeps the mulch fresh. Due to a speedier decomposition process, you’ll need to do this more frequently in hot and dry conditions. 

In wet or cold conditions, turning won’t be needed as often. Use anything from a rake and pitchfork to a garden shovel or spade for this task.

9. Monitor your lawn and plants

Keep an eye on the health of your lawn and plants. Regularly inspect them for signs of nutrient deficiencies or excesses and adjust your mulching practices accordingly. Organic mulch can harbor mold, fungi, and pests, especially if it’s too thick or damp. Remove the affected mulch if you see these problems. You don’t want to spread them on your grass accidentally.

10. Combine mulch with other amendments (if applicable)

For a more comprehensive approach to soil fertility and health, consider combining mulch with other soil amendments, like organic fertilizers or lime, based on the specific needs identified through soil testing. Some good organic fertilizers include animal and green manure, bone meal, wood ash, and cover crops such as vegetables.

FAQ about mulch

Do I have to remove old mulch before applying a new layer?

Unless the old layer of mulch is too thick, and you want to avoid suffocating your grass, you don’t have to remove it completely. However, it’s a good idea to loosen it up and give it a good mix to prevent compaction, which occurs when the layer becomes too dense and tightly packed.

How can I use a mulching lawn mower?

Mulching lawn mowers chop grass clippings into small pieces and leave them on the lawn, contributing to grasscycling, enhancing soil health, and reducing the need for fertilizers. Besides that, you won’t have to bag or rake grass clippings or deal with as many weeds, saving you time, money, and effort.

Is mulch safe for pets?

If you’re a pet owner, you know that dogs are particularly curious animals, and they’ll chew on anything they can get their little paws on (including mulch). When it comes to mulching in your yard, keep the following aspects in mind:

• Larger mulches can be a choking hazard, which is why you should either keep your pet away from the areas you’re mulching or select a finer, safer mulch.
• Always select natural options for safety purposes. Try to use organic household materials for composting or mulch that hasn’t been treated with chemicals. Remember that your dog may chew on anything you’ve treated with pesticides or herbicides.

Seasoned pros ready to help

Mulch is essential for nurturing healthy, beautiful outdoor spaces. If your DIY mulching approach just isn’t working, consider contacting a local pro for dedicated help. They can talk with you about your landscape design ideas, suggest the best mulch for your project, and make it happen.

Main Photo Credit: MatteoSunbreeze | Pixabay