When you think of much, you may envision tidy flower beds surrounded with beautiful layers of brown or red mulch. But mulch also works well for vegetable gardens!
Applying mulch to your vegetable garden can make it easier to manage while also increasing the aesthetic appeal. And when it comes time to select a mulch, you have a lot more options than the shredded wood mulch you find at landscape companies and big box stores.
I’m going to introduce you to the benefits of mulch and some of the materials you can use in your vegetable garden.
Why Should You Mulch Vegetable Gardens?
If you’re going to complete the work of applying mulch to your garden, you probably want to make sure your work is worth the effort. After all, planting, watering, and maintaining a garden is a lot of work already!
While applying mulch requires some extra work on the front end, it can ultimately lead to decreased work. That’s because mulch provides the following benefits to your vegetable garden.
Limit Weed Growth
When you apply mulch to your garden, you help limit the number of weeds.
Mulch can help prevent some weed seeds from germinating, which leads to fewer weeds. It can also prevent sunlight from reaching small weeds, leading to the weed seedlings’ deaths.
All types of mulch can limit weed pressure, but the thicker the mulch, the better.
Conserve Moisture
One of the major ways water leaves the soil is through evaporation. On hot and sunny days, the top inch of soil can dry out within a few hours after you water it.
Mulch can significantly limit evaporation and therefore decease the amount you need to irrigate. This can be especially beneficial in the summer or in dry climates where access to water is limited.
Limit Mud
When rain hits the soil, you end up with mud. And slogging through a muddy garden is no fun.
Your shoes end up caked in pounds and pounds of dirt that seems impossible to get off. Crops become covered in soil and require extra washing.
Applying mulch to the soil surface helps provide a barrier between wet soil and your feet and crops. That leads to a tidier garden that is easier to navigate and work in.
Increase Organic Matter
Many types of mulch are naturally occurring organic materials. Over time, materials like woodchips, hay, and pine needles will break down into smaller pieces, increasing the amount of organic material in the soil.
Increased soil organic matter is associated with numerous benefits, including improved soil structure, increased water-holding capacity, and soil aeration. And it helps hold certain nutrients in the soil until plants are ready to take them up.
It also provides a food source for beneficial microorganisms, leading to improved plant nutrient availability and resistance to certain types of diseases.
When to Mulch Vegetable Gardens
Since mulch helps conserve moisture and limit weed growth, the best time to mulch your garden is as soon as plants are in the ground.
If you plant vegetables from seedlings, try to mulch the plants right after you put them in the ground. However, make sure to leave a few inches of empty space around your plants to allow for airflow.
Since crops like beets, carrots, and beans are often direct seeded, wait until the seeds germinate before applying mulch.
Along with applying mulching to conserve moisture and prevent weeds, you can use it to protect the soil from erosion in the winter. If this is your goal, mulch your garden after you harvest fall crops.
Types of Mulch for Vegetable Gardens
When it comes to selecting mulching materials for your vegetable gardens, you can choose from lots of different materials. Here are some of the most frequently used types of garden mulch.
Hay
Hay is dry plant material that farmers typically harvest for animal feed. It can be made from plants such as alfalfa, ryegrass, clover, and oats.
Since hay is made from plants’ leaves and stems, it has a relatively low carbon to nitrogen ratio. That means it breaks down rather quickly and doesn’t tie up nitrogen, so you can use it as mulch without worrying about it causing nutrient-starved plants.
People typical sell hay in two forms: square and round bales. Square bales are smaller and easier to move, which makes them a good choice for smaller gardens. However, round bales are often a better choice for larger farms, especially if you have equipment to help you roll the bales out.
There are two main concerns about using hay as mulch: weed seeds and persistent herbicides.
If you apply hay that contains weeds, it can add weed seeds to your garden and lead to an increase in weeds. Therefore, it’s smart to buy hay from sources you trust have harvested from areas with few weeds.
While weeds are a problem, persistent herbicides can be an even larger issue. Farmers sometimes spray herbicides to kill weeds that don’t belong in their hay crop. These herbicides kill the weeds without affecting the hay crop.
These herbicides often reside on the hay after farmers harvest it. Some of these herbicides can remain on hay for up to three years after it was harvested.
If you apply herbicide-laden hay to your vegetable gardens, the herbicides can leach into your soil and impact many of your vegetables. These herbicides can result in deformed or stunted plant growth or even plant death.
Therefore, you should only use hay you’re sure has not been sprayed with persistent herbicides.
Straw
You may think straw and hay are the same thing, but they’re quite different. Straw is the byproduct that results after farmers harvest grains like wheat and rye.
Since it’s only made from plant stalks, it is more carbon-rich than hay. That means it takes more time to break down and provides less soil nutrients.
As with hay, you should ensure farmers didn’t spray straw with persistent herbicides that can harm your vegetable crops.
Leaves
If you live in an area with lots of deciduous trees, you know the leaf piles that appear each fall. Rather than disposing of these leaves, you can use them to mulch your garden.
Leaves are rather carbon-rich, but since they are so thin, they break down rather quickly. Shredding the leaves can speed up their breakdown time even more.
A related alternative to leaves is leaf mold. This consists of shredded leaves that have been partially composted. Although leaf mold takes a bit of time and work to make, it’s more biologically rich than leaves and also less likely to blow away.
Woodchips
Many types of woodchips can work well as mulch for vegetable gardens. This includes pine bark mulch, hardwood mulch, cypress mulch, and cedar mulch.
However, you should avoid using woodchips that come from black walnut trees. That’s because this wood releases a compound that can prevent the growth of other plants.
If you’re wondering about colored mulches, you’re not alone. The dyes used to create colored mulches—including black, brown, and red much—are typically safe for vegetable gardens. However, colored mulches are sometimes made from scraps of pressure-treated wood, which is considered toxic. Therefore, I like to err on the side of safety and use undyed woodchips from tree companies.
Pine Needles
If you live in the South or West, your landscapes may be dominated by coniferous rather than deciduous trees. That means you probably don’t have access to lots of leaves, but you may have access to pine needles, also known as pine straw.
Applying a few inches of pine straw to your garden will provide all of the benefits that other types of organic mulch provide.
Grass Clippings
You can use grass clippings as a mulch for vegetable gardens. However, these clippings tend to break down pretty quickly, which means you will need to reapply them every few weeks or so.
If you choose to use grass clippings as mulch, you should ensure the lawn they come from has not been spraying with persistent herbicides.
Coconut Coir
Tropical areas often have access to lots of coconuts and therefore coconut coir. This is the fiber that forms on the outside of coconuts.
Coconut coir is a carbon-rich material that can work well as an organic mulch for vegetable gardens. Applying a few inches of the material will limit weed growth and help conserve moisture.
Landscape Fabric
If you’re looking for an alternative to organic mulches, landscape fabric works well. This is a heavy plastic material that can be reused for multiple seasons before it becomes unusable.
Landscape fabric comes in various weights, such as 2.4 ounces and 3.5 ounces. The heavier the weight, the longer the fabric will last.
Water can penetrate through landscape fabric, but heavy rainfall will often lead to a bit of runoff.
Plastic Mulch
Many larger farms plant their transplanted crops into plastic mulch. This is a thin sheet of plastic that is applied to garden beds. Once the crops are harvested, farmers remove the plastic mulch.
Most types of this plastic mulch are disposable, but there is also a form of biodegradable plastic mulch that will break down when composted correctly.
This plastic mulch is often used on large-scale operations since it is easy to apply and easy to plant into. However, it doesn’t make a lot of sense for smaller gardeners to use.
How to Select Mulch for Vegetable Gardens
Since there are so many different types of mulch for vegetable gardens, it can take some time to choose the one that’s best for you. Some factors to take into consideration are availability, cost of the material, how easy it is to spread, how long it will last, and the nutrients it will provide.
First, there’s material availability. I always like to use what’s readily available, and that varies depending on the location.
In temperate areas with lots of deciduous trees, leaves are often readily available, and open agricultural plains typically provide lots of hay and straw. Therefore, it’s best to look around where you live and see what organic materials can serve as mulch.
Then, there’s affordability. If you’re mulching a large area, material cost is especially important. The cost of mulching material will depend on where you’re located, how much you purchase, and the quality of the material.
Next, you should consider how easy it is to spread the mulch. Woodchips may last longer than hay and leaves, but they’re also heavier and more difficult to spread. Shorter lasting mulch is often great for short-lived plants like lettuce and beets, but you likely want to choose longer-lasting mulch for perennial plants like asparagus and rhubarb.
My Preferred Mulch for Vegetable Gardens
I’ll preface my favorite type of mulch by reiterating what I’ve said above. The best mulch is what’s easily available to you! There’s no reason to pay for mulching material if you can access free materials.
Where I live, woodchips, leaves, and straw are readily available. I tend to use these free or low-cost materials along with landscape fabric.
Woodchips
I like to use woodchips to mulch pathways and perennial plants. They are readily available, slow to break down, and generally free from weed seeds.
However, since they’re carbon-rich and heavy to move, I typically avoid putting them on top of annual vegetable gardens.
When it comes time to find woodchips to use, I recommend a few options.
One option is to rent a wood chipper and make your own woodchips from downed trees and branches. A daily rental typically costs around $100.
Another option is to connect with local arborists, who often have access to almost unlimited amounts of woodchips. You can find local companies in your area and call them to see if they’d be willing to drop off woodchips. I find they’re often willing to do so since they would otherwise have to pay to drop off the chips at a local dump.
If you’d like to skip the work of calling companies, you can look into ChipDrop. ChipDrop is a national company that helps connect arborists with people looking for woodchips. Once you connect with an arborist in your area, you can receive a load of woodchips for free or limited cost.
Before you sign up for ChipDrop, it’s important to note that they typically drop a full load of woodchips at once. We’re talking buckets and buckets of woodchips. Therefore, they may not be the best service to use if you’re only looking to mulch a small garden.
Leaves
If you live in an area where leaves drop in the fall, you can probably find almost unlimited leaves. Sourcing them may take some work, but you can often find them for free, especially if you’re willing to collect them yourself.
One option is going around to individuals with lots of leaves in their yards. But if you’re looking for more leaves, try contacting landscaping companies or your town’s waste management department. Companies may be willing to drop leaves off at your garden, and you might be able to pick up leaves from the green waste department.
Deciduous leaves have a carbon to nitrogen ratio of about 60:1, so they won’t add much nitrogen to the soil. It also indicates that leaves will take a medium amount of time to break down.
I find that leaves will act as a good mulch for at least one growing season, as long as you apply at least a few inches of material. After a year, the leaves will break down, leading to an increase in soil organic matter.
If you want the leaves to break down quicker—and be less likely to blow away—you can shred them before using them as mulch.
I like using leaves to mulch around individual plants to trap moisture and limit weeds.
You can also layer a few inches of leaves on top of crops to protect them from cold winter temperatures. When spring arrives, gently rake the leaves off your garden beds to allow your crops to grow.
Straw
Straw is the byproduct that results after crops like wheat, rye, and barley are harvested. It’s rich in carbon but breaks down more quickly than woodchips. Plus, it’s much easier to move around than heavy woodchips.
Since straw is so easy to spread out, I like to use it to mulch around larger plants like tomatoes, cucumbers, squash, and peppers. Straw also makes a great mulch for garlic, which spends the winter in the ground.
Rectangular straw bales are often easy to find, especially during the summer and fall.
Landscape Fabric
I like landscape fabric since it’s reusable and easy to install. As long as you purchase a durable form of fabric, it should easily last three to five growing seasons. And installing it takes just a few minutes!
However, landscape fabric does have some cons. While it prevents weeds and keeps in moisture, it doesn’t add any organic material to the soil and must be thrown away once it begins to break down.
If you want to plant your plants directly into landscape fabric, you’ll need to first cut holes in the fabric. While you can cut holes using scissors or a knife, the cut edges will fray over time.
A better option is to burn holes in the fabric with a propane torch. If I’m burning holes at tight spacing—say eight or twelve inches—I like to create a template out of plywood.
First, I draw out the spacing on the piece of plywood. Then I cut out the holes using a jig saw. By the time I’m finished, I have a template that makes it easy to burn properly-spaced holes in landscape fabric.
When it comes time to burn the actual holes, I lay the plywood template flush against the landscape fabric. It’s best to do this on a flat and hard surface like an asphalt or gravel driveway. Then I step on the template and use the torch to burn holes in the fabric.
You can also purchase landscape fabric that already has holes in it.
Once your landscape fabric has holes in it, it’s time to install it in your garden. While you should apply most types of mulch after your plants are in the ground, you need to install landscape fabric before planting.
Lay the landscape fabric flat on the ground, ensuring there are no folds or wrinkles. Next, use landscape stables to hold the fabric to the ground. I find that placing staples about every five feet on both edges works well.
Alternatively, you can use bricks, rocks, or other heavy materials to hold the fabric in place.
Frequently Asked Questions
What Is the Best Bagged Mulch for a Vegetable Garden?
If you’re looking for bagged mulch to apply to your vegetable garden, the best option is undyed woodchips mulch. Cypress mulch, pine bark nuggets, and other types of wood will all work well.
Can I Use Shredded Paper for Vegetable Garden Mulch?
Shredded paper can be used as a vegetable garden mulch, but it will quickly break down. That means that you will need to reapply it quite often. Better mulch options include cardboard, woodchips, and straw.
Is Colored Mulch Safe for Vegetable Gardens?
Some colored mulch can be safe for vegetable gardens and some colored mulch should be avoided. The dyes used to create colored mulch are generally non-toxic, but colored mulch is sometimes made from toxic pressure-treated wood.
Is Rubber Mulch Safe for Vegetable Gardens?
You should avoid using rubber mulch on vegetable gardens since it is harmful to the environment and also difficult to remove. Wood mulch is a better alternative.
Choose the Mulch for You
There’s no doubt that mulching your vegetable garden is beneficial. However, there’s not necessarily one best type of mulch.
When you’re choosing a type of mulch for your garden, remember to consider product availability, cost, and ease of application. And don’t be afraid to experiment with a few different materials until you find the right mulch for you.