What’s the big deal about mulch? Sure, it looks nice, but is there any real reason you should invest the extra effort and money?
Well, think about it this way. Many people find that sleeping under a blanket regulates body temperature, provides a sense of security and promotes better sleep.
In the same way, a layer of mulch functions as a blanket for your garden and landscape beds. Most plants thrive under a cozy top layer that protects, insulates and nourishes.
Ready to learn more about mulch and how you can harness its benefits in your outdoor space? Let’s dive in!
Table of Contents
What Is Mulch?
Simply put, mulch is any material that acts as a covering for the top layer of your garden’s soil.
All materials fall into one of two main categories: organic and inorganic.
Organic materials were once alive and will fully decompose over time. As they break down, organic materials return to their basic chemical elements. These elements enter the soil, and plant roots can then absorb them for nutrition.
A few examples of organic materials include:
- Wood chips
- Tree leaves
As the opposite of organics, inorganic materials were never alive and will not break down to any significant degree.
Some examples of inorganic materials include these:
Common Mulch Materials
Some materials instantly come to mind when you think about mulch. Be it in the local park, a neighbor’s lawn or on TV, these materials have popular appeal going for them.
Though this list is by no means exhaustive, it gives you an idea of common materials you can expect to find:
- Pine bark
- Pine straw
- Grass clippings
- Chopped leaves
- Salt hay
- Red or black mulch
- Garden fabric
- Shredded rubber
- Black plastic
Gardeners are often a curious and resourceful lot. After all, the best way to learn is through experimentation, right? That sometimes means getting creative and working with what you have.
Some of these less-common materials may have more visual appeal than others. Nevertheless, they all perform the core mulch duties:
- Cocoa bean shells
- Shredded newspapers
- Burlap cloth
Why Use Mulch?
All right, so mulch is like a blanket for your garden. What exactly does that mean, and how does it work?
Let’s look at the benefits of proper mulching in detail:
Retain Soil Moisture
Just like any other living thing, plants need water to survive. Unlike many other living things that go in search of water, plants depend on moisture coming to them.
Since they act as a barrier between the soil and sunlight, all mulch materials help slow the evaporation process. Additionally, organic materials absorb and hold water, slowly releasing moisture into the underlying soil.
In short, proper mulching techniques keep moisture available in the upper levels of soil, right where your plants need it.
Is there a never-ending task that gardeners hate more than dealing with pesky weeds? (Although dealing with pesky insects comes close.)
Weed seeds lurk in almost any garden plot, but once again, mulch comes to the rescue. By covering these seeds with a layer of mulch, you take away the sunlight needed for germination. Thus, fewer weeds.
Insulate Plant Roots
While any plant will benefit from a layer of mulch, it can be especially helpful for annual vegetables and flowers.
A single growing season usually isn’t enough time for a plant to develop an extensive root system. As a result, annuals have shallow roots that are more vulnerable to damage from ambient temperature fluctuations.
Think back to the blanket analogy we used earlier. A layer of mulch acts as a protective covering for these delicate roots.
Mulch can help regulate soil temperature in two ways:
- It acts as a barrier to prevent the harsh sunlight of summer from overheating the soil
- It prevents heat loss in the cooler days of spring and fall
Note: This is not true of landscaping rock. Rock amplifies the ambient temperature into the soil, causing even wilder temperature changes.
Prevent Soil Erosion
Dirt may seem plentiful, but the reality is that topsoil is a precious resource that can quickly become scarce.
Laying mulch helps keep your soil from washing away in rainy weather or blowing away in dry conditions.
You may need to spend some extra time cleaning up mulch after a rain or wind storm. However, more of your all-important soil will stay where it belongs.
Enrich Soil with Minerals and Nutrients
Organic materials contain high levels of vital nutrients, like nitrogen, potassium and salt. The decomposition process breaks chemical bonds within the organic material, making these basic nutritional elements available in the soil.
Plant roots absorb these nutrients and the rest is history: Vibrant green leaves, abundant blossoms and increased production.
Improve Soil Texture
Some of us live in areas with heavy clay dirt, and others have thin, sandy topsoil to work with.
As it breaks down over time, mulch matter mixes with the soil. This usually leaves the soil with better drainage and airflow capacity.
Note: Most inorganic materials are strictly a soil top covering, and they don’t have any significant impact on soil conditions.
Add an Attractive Finish
Depending on your style preference, you may choose shredded cedar, pine bark, cocoa bean shells or something completely different.
No matter the material, a fresh layer of mulch gives your garden and landscape beds a fresh, manicured appearance.
How To Use Mulch
No matter if you’re growing vegetables or beautifying your landscape, make your plants happy with thoughtfully applied mulch.
Here are the details:
How Deep Should Mulch Be?
In any garden or landscape setting, the general depth recommendation is 2 to 4 inches.
Keep in mind that most materials will settle over time. If you apply a 4-inch layer, you’ll end up with one that’s about 3 inches deep after a few weeks.
Most vegetables and flowers thrive with a mulch layer that’s about 2 inches deep. So aim to spread a layer that’s roughly 3 inches thick during your initial application.
What Tools Do You Need?
Many homeowners choose to apply mulch to their garden or landscape themselves. Besides saving money, you can also enjoy nature and get a good workout at the same time.
In addition to some elbow grease, you’ll need just a few basic garden tools:
- Sturdy, comfortable work gloves
- A shovel or garden fork for scooping and spreading mulch
- A wheelbarrow saves time and spares your back
- A garden rake for creating a smooth, even surface
- A source for your favorite music
- Frosty adult beverages
Oh, sorry! Those last two are on my own personal list, ha ha!
Depending on how large your work area is, block out an afternoon or weekend.
Try to schedule your work during a sunny stretch of weather. Dry mulch is infinitely easier to work with, and sunlight can help prevent mold growth.
The Application Process
All right, you’re ready to get to it!
Follow these steps to apply mulch like a pro:
- Gather all necessary supplies.
- If you’re working with large piles of bulk mulch: Use a shovel or pitchfork to fill a wheelbarrow with a manageable amount. Take it to your work area.
- If you’re working with bagged mulch: To cut down on trips, lay bags directly in front of your work area. If you want, you could also over bags in your wheelbarrow and then take them to your desired area.
- Using your shovel or pitchfork, dump a few scoops of mulch on your work area.
- Use a garden rake to spread the mulch in a smooth layer at your desired depth.
Always leave a small amount of bare ground immediately around the plant stem. You don’t want to choke your plants! Remember, your primary goal is to support and protect plants at the root level.
Don’t Make This Mistake With Your Trees!
You know what you don’t want when mulching around trees? A “tree volcano.”
What’s that? These two photos help illustrate a volcano vs. proper application:
See how the mulch is heaped up tightly around the base of the tree in the first photo? This is a tree volcano. It’s a popular technique for certain landscaping tastes, but it can also be harmful to the tree.
One of mulch’s primary purposes is to retain moisture. Great for soil, not so great for tree trunks. Exposure to excessive moisture can weaken the bark, leaving trees susceptible to fungal growth.
Secondly, mounded mulch can make an attractive home for pests, potentially leading to an infestation.
The second photo shows a better way to care for trees. Leave a 4- to 6-inch ring of bare earth around the tree’s base. Gradually build a deeper layer of mulch as you work outwards from the tree.
The method has several goals in mind:
- Promotes proper drainage around the tree trunk.
- Exposes bark to healthy airflow.
- Keeps mulch-loving pests farther away from the tree’s trunk.
Choosing The Right Material
How much upkeep are you willing to do What kind of plants are you growing? What does your ideal landscape look like?
These questions can help guide you in choosing the right material for your garden and landscape beds.
In this section, we’ll cover these areas in detail:
- Vegetable gardens
- Shrubs and Trees
1. Vegetable Gardens
What materials can you use for your vegetable beds? In general, organic materials that break down quickly are your best choice for maximum harvests.
Consider using some of these suggestions.
When it comes to choosing the best mulch for vegetable gardens, compost is hard to beat.
Most of the time, making compost entails using a wide variety of ingredients. This can include kitchen scraps and yard refuse. Thanks to this mixed bag of raw materials, your plants will get a balanced diet with plenty of necessary nutrients.
Compost also quickly mixes with the soil itself to promote good drainage and airflow.
You know that grass left on your lawn after mowing? Spread some in your garden! These clippings are another material that provides good plant nutrition and moisture retention. Best of all, they’re free and readily available.
However, grass clippings have a tend to get matted over time. For best results, use a light touch and spread grass clippings in a thin layer around plants.
Note: Only use clippings from lawns that haven’t been treated with any herbicides. Residues from these chemicals can inhibit vegetable growth and potentially contaminate your harvest.
Shredded or Chopped Leaves
Leaves provide a great long-lasting, protective soil top dressing. Just make sure to let your leaves age for several months before applying them to your garden beds.
Why? Tree leaves contain phenols, which are anti-microbial agents. A healthy population of friendly microbes are essential for a productive garden, so you don’t want to kill off the good guys.
Since phenol levels in leaves decrease over time, aged leaves are safe to use in your vegetable garden.
Black Plastic Sheeting
Plants that thrive in hot weather typically do best with a covering of black garden plastic. These plants include tomatoes and peppers. Particularly through spring and early summer, garden plastic increases soil temperature and can boost your harvest.
However, rain or hose water tends to run off black plastic, so check the soil’s moisture level frequently.
Other Vegetable Garden Materials
The materials listed above are the most common organic mulches for vegetable gardens. Some people have found great success with these alternative materials:
- Salt hay
Mulch often serves a dual purpose in flowerbeds.
For one, it provides a lovely backdrop to colorful blossoms and vibrant foliage. Secondly, organic materials can feed your flowers and encourage abundant blooming.
Here are some options to consider for your flowerbeds:
Compost or Manure
Compost and manure both provide a wealth of nutrition for your plants. Each of these materials can also help improve poor soil, like those with a sandy or clumpy sod texture.
While almost any flower will greatly appreciate a layer of compost, there are a couple of downsides.
Firstly, compost mixes with the soil quickly, so you’ll have to reapply often. Second, with its dark brown color and crumbly texture, compost doesn’t have the “wow factor” of other materials.
Cocoa Bean Shells
A less common choice, cocoa bean shells provide a unique texture that adds visual interest. The rich brown color is also a beautiful backdrop for vibrant blooms.
The downside to cocoa bean shells is that they tend to migrate easily. Using a rock or short fencing border can help keep shells where they belong.
Pine straw, which consists of fallen pine needles, boasts a rich reddish color and fluffy texture. This material is especially popular in the Southern states, where pine trees are numerous and fallen needles abound.
As they break down, pine needles add a small amount of acid to the underlying soil. Using pine straw for mulch is a fantastic addition to beds of acid-loving flowers. Azaleas, hydrangeas and daffodils are a few examples of flowers that thrive in acidic conditions.
Despite their small size, pine needles tend to be fairly low maintenance. Even though it decomposes slowly, pine straw tends to take on a weathered, silvery-gray shade over time.
Wood chips and shreds are consistently popular options, and for good reason. Wood is usually inexpensive, readily available, easy to apply and comes in an array of colors.
Whether you prefer a natural shade or a dyed option for a striking contrast against blooms, wood mulch delivers.
As far as upkeep goes, wood materials require moderate effort for maximum impact.
All wood will eventually take on a weathered gray hue, and you’ll probably need a fresh application every couple of years. However, cedar and pine bark have a naturally rich color that tends to stay true for a few seasons.
Additionally, you may have to rake stray chips back into place after heavy rain or wind.
3. Shrubs and Trees
When planting new shrubbery or tree saplings, add a generous layer of nutrient-rich organic mulch. Compost or manure can be great options to give your new shrub or tree a healthy head start.
Most of the time, visual appeal is the primary reason for mulching around established shrubs and trees.
With their deep root systems, older shrubs and trees have access to moisture and nutrients from deep within the earth. As such, they are likely to be fairly tolerant of almost any mulching materials.
These are a few popular choices:
While mulching brings many benefits, with all the good things come the prospect for a few downfalls. The good news is that most of these problems are minor. What’s more, a few steps on your part can quickly resolve most issues or prevent them in the first place.
Here are some potential problems to be aware of and how you can keep your mulch looking spectacular.
Wood Alcohol Syndrome
Wood alcohol syndrome occurs when wood mulch gets wet and has inadequate airflow. In these conditions, anaerobic microbes turn organic material into alcoholic compounds.
When you apply this mulch near plants, it has a toxic effect that causes leaf drop and discoloration. Established shrubs and perennials will likely be fine in the long term, but younger plants may die.
This issue is most common in bulk quantity mulch that sits in large heaps. But it can also occur in bags that have sat unopened for a long time.
Wood alcohol syndrome may sound extremely serious, but it’s actually easy to remedy:
- First of all, smell the mulch before you apply it. A strong alcoholic scent indicates that you have a problem.
- Spread the mulch out, preferably in a sunny area, and let it dry. Exposure to oxygen stops the anaerobic alcohol production in its tracks. Once the smell is gone, the mulch is perfectly safe to use.
- If you’ve already applied questionable wood material, water the affected area thoroughly. This will help wash away toxins.
- If your plants are discolored or losing leaves, prune away the damaged areas.
Mold or Fungus
This is primarily a concern with wood-based materials.
As wood decomposes, it can become a hospitable environment for mold and fungal growth. Some of these growths, such as slime mold, won’t harm your plants or landscape.
On the other hand, some fungi may damage plant leaves or release spores that travel to other areas of your yard.
Remove wood material that shows signs of mold or fungal growth and replace with fresh material.
Also, mulch that’s spread too thickly is at a higher risk for mold or fungus. So make sure to apply mulch at the recommended depth.
One of your primary goals in mulching is to keep moisture in the soil. However, it’s possible to have too much of a good thing.
In general, vegetables and flowers prefer moist, well-draining soil. Adding too much mulch can trap water in the soil, leading to root rot from excessive moisture.
Spread mulch to the recommended depth of about 3 inches. Additionally, don’t lay mulch directly against main plant stems or trunks.
The nooks and crannies between individual pieces of mulch can make an inviting home for insects and small rodents. This becomes especially problematic if you mulch too thickly.
Wet soil conditions from over-mulching can also attract harmful pests like slugs or snails.
Avoid excessive mulching, and be vigilant for signs of pest activity.
As you probably noticed, several of these problems come from applying too much mulch. Follow the general 3-inch depth recommendation, and you should be able to avoid most issues.
Where To Find Quality Mulch
So now you know why proper mulching is important and you have an idea which materials work well for various types of gardens.
So where can you get the materials you need? The good news is that you have several sources for high-quality mulch.
National home store chains typically carry a good assortment of bagged mulches. You’ll most commonly find these materials:
- Wood-based materials, including cypress, hardwood, pine bark and dyed wood products
- Landscaping gravel, pebbles and river rock
- Garden fabric and black plastic
- Shredded rubber
Depending on the region, you may also find pine straw as a stock item. If you can’t find it on the shelf, you may be able to have it shipped to the store for pick-up.
On the other hand, specialty materials like cocoa bean shells or salt hay may be scarce.
If you’re working with a large piece of ground, a nursery will probably be your most cost-effective option. Most nurseries sell mulch in bulk quantities, and they will often deliver it to your home.
Wood-based materials are the most common bulk options. Some local specialty companies may also produce commercial compost.
Mulch from a nursery is likely to be of the highest quality. Additionally, the staff are typically very knowledgeable and can give you expert advice.
To top it off, you can also support a local business.
Landscaping or Tree Care Services
Businesses that trim away tree branches or brush are usually all too happy to get rid of freshly chipped wood. You can often get wood chip mulch for free or at a low cost.
While aged wood chips or shreds are excellent in various settings, you need to use more care with fresh wood chips. As newly-cut wood begins the decomposition process, it can leach nitrogen from the soil.
If you have muddy, slippery paths through your garden, fresh wood chips can be your perfect solution.
Is there anything you can’t buy online? Yes, but mulch isn’t one of them.
While there is a surprisingly wide selection available online, it doesn’t compare with what you’ll find shopping in person. However, online resources can be perfect for tracking down specialty materials that aren’t available in stores near you.
You’ll likely pay a higher price for the convenience of ordering. And definitely make sure you check the shipping costs before placing your order!
All in all, ordering mulch online is probably best suited for small or very specialized projects.
Make Your Own
Compost is a fantastic material for vegetable and flower gardens, and the price is right if you make it yourself. Construct a compost pile or use a composting bin to turn kitchen scraps and yard waste into next year’s mulch.
In reasonable amounts, yard waste, like grass clippings and chopped leaves, can be a nutritious and inexpensive mulch.
You may also find some other materials around the house if you’re willing to get creative. As we mentioned earlier, cardboard, seaweed or newspapers can all be options.
How Much Does Mulch Cost?
Your total mulch cost will depend on a few factors:
- The material you choose
- How much you need
- Whether you hire help for the job
According to HomeAdvisor.com, the average homeowner spends $175 to install a 3-inch layer on mulch on a 500 square-foot garden.
How Much Mulch is in One Yard?
We’re going to be talking about cubic yards a lot here. So first of all, we’ve got to define our terms.
A cubic yard of mulch contains 27 cubic feet. With one cubic yard, you should be able to cover an area of 100 square feet with 3 inches of mulch.
To give you a comparison, a bag of wood chips or shreds typically contains 2 cubic feet. Bagged landscaping rock usually contains less than 1 cubic foot.
Ugh, these numbers make my head hurt! How about you? For people like us, here’s a handy conversion calculator:
Note: All prices listed are averaged across the United States. Depending on the region you live in, your costs may be lower or higher.
Wood-based mulches are usually the most inexpensive options available. Even within this category, though, prices vary widely.
Inorganic materials tend to cost the most. The average homeowner spends about $120 for a cubic yard of shredded rubber. Bulk delivery charges aren’t included here, so be sure to figure in any extra charges that may apply.
According to data from KompareIt.com, these are some common prices for bagged mulch:
As a generalized price range, wood mulch will run you anywhere from about $3 to $7 per bag.
Landscaping rock is usually about $4 to $5 per bag. However, it’s important to note that one bag of rock doesn’t cover much ground area.
If you plan to go the DIY route, your only extra costs will be any tools you need to purchase. If you already own all the necessary tools, this isn’t a concern.
Landscaping services charge varying rates, and the cost will depend largely on the size of the job. HomeAdvisor places the average installation cost at $35 for each cubic yard.
Your long-term costs depend on the material you choose and your DIY capability.
Plan to replace organic mulch somewhere between every one to three years. Also, factor in whether you’ll lay the mulch yourself or hire a professional.
Inorganic materials like rock and shredded rubber cost more at the outset, but they break down slowly or not all. This extends your investment for years, and the long-term costs are typically less than those for organic materials.
Frequently Asked Questions
1. Which Materials are Best for Kids and Pets?
Although mulch seems like it should be pretty harmless, some materials can have hidden dangers.
For example, shredded rubber and dyed red or black mulch could contain hazardous chemical residues. And cocoa bean shells could make dogs ill if they chew the shells.
Here are some safer choices to consider:
Hardwood. Hardwood mulch is a fantastic all-purpose material.
Pine Bark Nuggets or Shreds. Pine bark is typically inexpensive, hypoallergenic and easy to find.
Cedar. Cedar has unique chemical properties that provide a natural defense against insects and decay.
However, there are two areas of potential concern with cedar.
- Certain chemical compounds in cedar can irritate respiratory allergies or trigger a form of asthma for some people. Use a different material if your child suffers from allergies or breathing problems.
- Cedar has a strong natural scent which some people find off-putting. To find out if this might be an issue, have your child smell cedar mulch at the store or nursery. They should be able to tell you right away if they don’t like the smell.
2. Which Materials Last the Longest?
Since they resist decay, inorganic materials have, by far, the longest lifespans.
Landscaping rock and shredded rubber are two options that should last for upwards of a decade. In addition to their longevity, these materials are also extremely low-maintenance.
Among organic materials, large pine bark nuggets and cedar shreds maintain their shape and color for the longest time.
3. Do You Need to Remove Old Mulch Before Adding a New Layer?
In most cases, removing as much old mulch as possible first will make your new application look its best.
For instance, applying a new layer of wood chips or shreds over the old may look good at first.
However, wood tends to take on a grayish color from weather exposure. Old chips have an annoying habit of making their way to the surface and dulling the vibrancy of fresh chips.
So while old mulch won’t hurt your plants or soil, leaving it in place can look unattractive.
4. Are There Areas You Should Avoid Mulching?
Thanks to the variety of materials available, you should be able to find an appropriate mulch for almost any area.
Here are some good options for challenging landscape features:
Slopes. Water runs downhill, and you want to avoid materials that can easily get swept away.
Even though it’s very lightweight, pine straw tends to tolerate flowing water quite well. River rocks or larger stones are also great choices.
Areas prone to flooding or standing water. Some materials can float away, leaving you with a mess and a bare patch of soil. Thanks to the hefty size, rocks are excellent for water-logged spots.
5. How Do I Prevent Weeds from Growing?
While mulch helps to deter weeds, it doesn’t completely eliminate them. Use these strategies to stop weeds from growing in your mulch.
Herbicidal sprays. Before applying their material of choice, some gardeners treat the soil with an herbicide to kill any existing weed seeds.
This technique is usually effective, but it also introduces harsh chemicals into your garden.
There are organic weed sprays that contain fewer controversial ingredients than conventional products. While they tend to be slightly less effective, they can still help you keep the majority of weeds under control.
Weed barrier. Laying black plastic sheeting or garden fabric before you mulch is a great way to reduce weeds. Not only do these products keep any existing weeds from reaching the surface, but they also prevent new seeds from reaching the soil.
Using a weed barrier is an excellent option in many ornamental beds. In particular, landscaping rocks are more prone to weeds than other materials. So using a weed barrier is an essential step for these beds.
However, weed barriers may not be an appropriate choice for all beds.
For example, part of your goal in mulching your vegetable garden is to add beneficial nutrients to the soil. A weed barrier stops this process in its tracks.
Vigilance and manual removal. To put it another way: Keep an eye out for new weeds and pull them as soon as possible.
You have a couple of factors in your favor here:
- Mulch is a fairly loose material
- Weeds often struggle to develop a strong root system in the extra depth
As a result, pulling weeds from your mulched beds should be easy, especially if you do it right away.
We’ve written a much more in-depth article on this, so stop by our post on how to stop weeds from growing in mulch to learn more.
6. What Time of Year is Best?
Typically, the middle or latter part of spring is the best time to mulch.
If you live in an area that experiences true winter, wait until the ground naturally thaws before you apply any mulch material. By adding a top dressing too early, you risk trapping frost in the ground and delaying your growing season.
If you’re mulching for aesthetic purposes, a refresh in the fall can help keep your landscape looking fresh and polished.
7. Do You Need to Prepare the Soil First?
There are some areas where you can simply lay down a layer of mulch and call it a day. Areas around established trees and shrubs are two of these instances.
In other circumstances, a little preparation can yield big benefits.
Fertilizing. Pine straw, wood chips and pine bark are a few examples of materials that break down slowly. If you choose these materials for your vegetable garden or flowerbed, fertilizing the soil first is a good idea.
Weed Barrier. If you’re planning to use landscaping rock, preparing the area with a weed barrier is a must. Not only does the barrier prevent weed growth, but it also keeps your rocks from sinking into the soil.
Let’s summarize what we’ve learned here:
- Wow! There’s a lot of different mulch materials to choose from out there!
- The right one for you depends on the plants you’re growing and your individual production or landscape goals.
- Mulch can beautify your space and boost plant health in the short term, and it can also improve your soil conditions for the future.
- Proper application techniques yield the best results and help you avoid irksome problems.
- You have several possible sources for a high-quality product.
- Think about your preferred material, how much you need and any installation costs when figuring out your budget.
So there you have it: Your complete guide to mulch mastery.
What did you think? Is there anything we missed here, or do you have any other thoughts or questions?
We’d love to hear from you in the comments!