What is mulch for?

Why do we bother mulching around trees, shrubs, and perennials? It is often expensive, has to be frequently re-applied, and doesn’t even totally stop weeds. Do we only use it because it looks pretty? While it may look nice, the real purpose behind applying organic mulch is not merely aesthetic, nor is it solely weed prevention. Mulching around plants creates one of the best environments for growing in our urban soils.

Studies conducted at the Morton Arboretum in Chicago have shown that applying organic mulch increases the organic matter in the soil. Microorganisms that are naturally present in the soil degrade the mulch depositing decomposed organic material at the plants’ roots. This organic material provides necessary nutrients and holds moisture in the soil for the plants. Access to these nutrients and moisture is visible above ground in the healthy growth and appearance of the plant. It is the microbial degradation of the mulch that necessitates reapplication every two – three years.

As this degraded organic mulch is incorporated into the soil, it reduces compaction significantly. Excessive compaction is a common issue in urban soils that have been stripped, turned, and driven on repeatedly. Compaction reduces air between soil particles, limiting the roots’ ability to breath, causing stress on the plant. “Soil compaction is one of the biggest problems a tree root can have.” Compacted soils significantly limit the growth of plants, particularly trees and predispose them to infections. Regular mulching, has been shown to reduce compaction considerably in only a few years.

The benefits of mulching: increased organic matter, nutrients, water, and reduced compaction, can be realized using a wide range of materials. All of these materials need to be readily compostable organic (carbon containing) substances. Materials that are often used are wood, straw, evergreen needles, seed hulls (cocoa beans, coconut husks), and compost. Some of these materials, such as straw and wood chips take longer to decompose and consume more nitrogen thereby reducing their benefit. Evergreen needles may acidify the soil which can be troublesome for certain plants. Some seed hulls are toxic to pets and decompose completely in the same season reducing their extended benefit. Compost does little to prevent weeds and sometimes encourages them. Our preferred organic mulch is shredded hardwood. This product provides benefits up to three years and should be applied 3” deep around the absorbing roots of the plant. When mulch has noticeably thinned, it is time to reapply to continue benefiting the plants.

Coconut husks (coir)

Wood Chips

Pine Needles

Shredded Hardwood

Thinned mulch, reapplication overdue

Mulch after reapplication with shredded hardwood mulch

In addition to the underground benefits from regular mulching there are other, aesthetic reasons to mulch. It provides the landscape a fresh, new look, much like newly painted siding, or clean seal-coating. It can also prevent many weed seeds from germinating depending on the product chosen. However, from the plant’s perspective, the decomposition activity occurring underground is far more important. It affords the plant the best possible access to nutrients, air space, and water in otherwise limiting soils. Reapplication of mulch will produce a substantially healthier, more productive plant in your landscape.

By: Catherine Nickelson | Horticulturist | Arborist
Posted 08/18/2017


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There’s a fair chance you’ve been working on your yard or in your garden and either thought about spreading some mulch around or have already done so. Have you ever, though, stopped to ask yourself “What is mulch and why do we use it?” I know, on numerous occasions, I’ve spread the stuff around without really knowing its purpose, just liking the look of it.

In truth, mulch is very important for the health of your landscaping. It keeps moisture in, it controls weeds and prevents soil erosion, and it keeps your ground generally healthy, among other things. Mulch is pretty incredible stuff, and any garden or yard which isn’t making use of it is definitely missing out.

What is mulch, though? That’s a complicated question due to the fact there are so many different variations

Table of Contents


All the different types of mulch don’t just exist for aesthetic reasons. Some hold in moisture better while others keep the soil healthy. The kind of mulch you need can vary greatly depending on what your goal is with the area in which you are using it. In order to figure that out, you’ll need to learn what each type of mulch is in the first place.


Mulch is a general term for pretty much any type of material you would use above soil in landscaping. Garden mulch, specifically, would be the kind you use in your garden. This can include pretty much any type of mulch, but some definitely work better than others. Some also look better than others.


Looking to do your part by helping to reduce, reuse and recycle? If so, rubber mulch could be a good thing or you. While it can work in a plant-growing situation, it perhaps serves its best purpose as an outdoor flooring material.

Rubber mulch is made up of rubber from tires which have either been chopped up into nuggets or rubber which was shaved from semi-truck tires before they are retreaded, which are called buffings. Though they aren’t necessarily organic, they do serve some organic purposes.

For instance, rubber mulch has the unique ability to insulate soil from heat when compared to wood mulches. Additionally, since rubber is a non-porous material, no moisture is lost as it makes its way through the mulch layer into the soil below.

As for non-gardening uses, rubber mulch has earned great respect as a material suitable for playgrounds. Instead of using a wood mulch on the floor of the playground, rubber mulch is often used, which can make the area safer for playing children. Thanks to the elasticity associated with rubber, using this material to break falls is better than other types of outdoor flooring.


No water loss
Good insulation
High elasticity
Slows growth of weeds
Lasts up to 10 years


Does not enrich soil
May contain chemicals
Organic if burned


Bark mulch, as the name implies, comes from the bark of trees. More specifically, it’s bark which has been harvested from various conifers, such as pines and firs. Bark mulch is definitely aesthetically pleasing. The large chips of bark catch the eye quite well, and they have some good growing benefits, as well.

For instance, it doesn’t allow moisture to evaporate very well, helping to conserve the stuff. Also, as it ages, it can provide nutrients back into the soil. There are definitely some cons working against bark mulch, however. It is quite light, so it can be moved around by wind or rain.

Additionally, it can be somewhat fragile and prone to splintering. You can get bark mulch in a shredded format, if the chips aren’t your style, which could better suit your purposes and holds its own benefits. It can retain moisture even better than the chip form, and it’s smaller so it can decompose faster in order to help out the soil.

Looks nice
Conserves water
Decomposes for nutrients
Lasts up to seven years

Doesn’t stay in place


Hardwood mulch is potentially very inexpensive. Since it’s basically made up of refuse from tree trimming jobs and old wooden stuff, finding the material which has been shredded into mulch can be as simple as making a few calls and taking it away for free. Of course, your mileage on this may vary.

In gardens and other landscaping situations, hardwood chips can be used around plants which don’t require a whole lot of acid, as the stuff breaks down into an alkaline form after time. Plants which need more acid could require some special acid-increasing fertilizer in that case.

I suppose that’s a bit of a positive and a negative, depending on the plants you’re using. Another downside to using hardwood mulch is how it changes over the years. It is prone to turn gray after some time, at which point it will need to be raked up and turned. This also means it won’t be so good after just a couple years.

On top of that, hardwood chips make for a great buffet for termites, so having hardwood mulch in a garden which borders your house isn’t advisable at all.

Good for alkaline-loving plants

Turns grey
Only lasts up to two years
Good food for termites
Bad for acid-loving plants


Hemlock trees get a bad rap. There is a bit of a case of mistaken identity involved with them, as many people believe using their bark or wood as much can be dangerous, since hemlock is poisonous. Hemlock trees, however, are not what’s poisonous. The poisonous stuff is a completely different animal. Well, not an animal, but a wild bush with big leaves and a purple stem.

It’s really too bad this stigma exists, because hemlock mulch is actually fantastic. It’s a hardwood mulch, so it carries all of the same benefits and issues as other hardwoods, but it has some special qualities, as well. It seems the tree contains a large number of tannins, and these tannins keep bugs and such from digging into your soil and munching on your plants. It’s also quite nice to look at.

Keeps pests away

Short lifetime
Good food for termites


It is possible, and actually not a bad idea, to use leaves which have fallen from your trees as mulch. This costs you absolutely no money, doesn’t take a whole lot of work, and works pretty well. However, there are a couple caveats to keep in mind when using leaves as mulch.

Once nature has done its thing and made all your leaves fall from your trees when autumn hits, get your rake and gather them up. Before using them as mulch, you’ll need to shred the leaves first. This can be done using a shredder, a mulching lawnmower or a leaf blower which has a vacuum function.

Using a layer of leaves which is too thick can have some unintended negative effects on your soil, such as keeping air and water from getting down into it. At the same time, they can also hold too much moisture in, allowing for the potential of rot and fungus issues.

You can first apply a thin layer of complete leaves, but shredding the rest before putting them onto your soil will allow for better passage of air and water, making sure your soil stays as healthy as it needs to in order to allow your plants to thrive. Any leaves you don’t use can be used as compost for gardening projects down the line.

Keeps moisture in
Decomposes into nutrients

Needs to be shredded first
Could keep in too much moisture
Could block too much air and water


Were you aware glass can be used as a mulch? Almost exclusively decorative, glass mulch is made up of recycled glass which has been tumbled to remove any sharp edges. It can be placed pretty much anywhere one might put rocks or pebbles in a landscape, but it has the unique effect of being very pretty. It usually is made up of glass of all kinds of colors, creating a look which is truly incomparable.

Unfortunately, it’s a little on the expensive side. Way more expensive than any of the organic mulches, for certain. Using glass mulch for plants requires plants which can handle rocky soil, and there should be some landscape cloth or plastic between the glass and the soil to keep the mulch from sinking in too deep over time.

Unique look
Good water penetration

Requires barrier between mulch and soil


Lava rock mulch, sometimes called pumice mulch, is pretty handy, and functions similarly to rubber mulch in that it allows for proper water flow without absorbing any of it. Also like rubber, the lava stone helps the ground stay warm, though not in the same way. Whereas rubber serves as an insulator for the heat, lava rock absorbs the heat throughout the day, then helps the plants by keeping things warm through the night.

It also is good at keeping moisture in and, with the help of a barrier like fabric or plastic beneath it, it can keep weeds from getting into your garden. On the opposite end of the spectrum, the stuff is pretty lightweight, so it may not stay still, and it’s tough enough to do some damage to your lawnmower, should some of it end up in the yard where it isn’t wanted.

Also, you need to be careful when using lava rock to check it from time to time. The material can build up between the rocks themselves which could inhibit air and water from reaching the soil properly.


There’s a fair chance you’ve seen some red mulch in your lifetime. It’s, if you couldn’t tell, the super red stuff you sometimes see in someone’s yard, or in the landscaping of a business. Sure, you can get red mulch naturally, depending on the origin of the stuff. Many bark mulch types can look reddish thanks to having come from red-barked trees, but often, the red mulch you’re seeing has been dyed.

In a great many cases, red mulch has a similar origin to hardwood mulch, often coming from the leftover materials of construction jobs and such. Because of this, and because of some of the more unsavory materials which can be used as dyes, they’re often not recommended for growing situations, as red mulch can potentially leak harmful chemicals into the ground, causing damage to nearby plants.


If you’ve ever heard the term enviro mulch and weren’t sure what it meant, you’re not alone. This isn’t a term thrown around too often, but it’s something which does exist and is rather specific. Enviro mulch is basically the same as any other sort of wood mulch, such as bark or hardwood, for instance, but it is exclusively made up of recycled materials, be that old wood, cardboard boxes, paper, or whatever else out there started out as a tree.

Just as with bark or hardwood, it is often found dyed into various shades, and, just as with its counterparts, it carries the same positive and negative benefits, but this time you’re certainly doing your part by giving new life to material which may have otherwise been wasted, left rotting away in a landfill or something.


Certain mulches have the capability of being dyed. It isn’t unusual to see red, brown, black and even green mulch from time to time. Is dying the mulch safe for the plants on which it will be used? Are there certain dying methods which may be better than others? Is there a benefit to using a dyed mulch over one which is more natural? Let’s take a look.

Vegetable-Based Dye

True to their name, vegetable-based dyes are created using different types of plants, just as dyes were in olden times. These are great for any type of garden, because if there is any sort of leaching going on with the materials used to dye the mulch, it’s not going to be a bad thing for your plants.

Iron-Oxide-Based Dye

Since red is a pretty popular color out there, mulches dyed using iron-oxide-based dyes are pretty common. It may, in fact, by the most common type of dye. It is created by combining iron and oxygen, and using the resulting compound to color the mulch. If you weren’t aware, iron-oxide is basically rust, hence the rust-like color of the mulch.

While the runoff from this does go into the soil, it isn’t necessarily a bad thing. It just means there’s more iron for your plants, which can actually be a benefit to certain varieties of plant which may need a little more metal in their systems.

Carbon-Based Dye

Any mulch which has been dyed black was likely dyed using a carbon-based dye. This color is acquired by using carbon black, which is the byproduct of incomplete combustion of a number of items. Many of the sources aren’t exactly edible or good for plants, but one source is: vegetable oil.

Using carbon black produced from vegetable oil, mulches can be dyed and not have any sort of negative impact on the soil beneath them. This is especially important if it’s being used as mulch around plants which provide food, such as those in a garden.

Many countries use carbon black for even more things, such as the coloring of food packaging and trays. When mulch dyed with carbon black breaks down, it releases carbon into the soil, pretty much in the same fashion as burying charcoal.

Dying Mulch Yourself

Is your mulch looking a little under the weather? Spruce it up by giving it a little of that color it deserves. This process is moderately new. In general, most people will throw away their dull mulch and replace it with new good stuff, or just cover up the old with the new.

Doing the deed yourself isn’t especially difficult, but it does take some planning. First off, you need to choose your dye from one of the many available colors. In order to have the best effect, you should try to get a dye which is near the original color of your mulch in case you miss a spot or two.

If there is rain in the forecast, continue waiting a day or two for sometime when you’re sure to have clear skies and bright sun for at least six hours. Once you spray the dye onto your mulch, it’s going to need time to dry, and rain will just come in and mess up all of your hard work.

Obviously, dye is designed to last, so making sure it only goes where you want it to go is a big deal. If you’re dying mulch along a sidewalk or driveway, do whatever you can to keep it from getting onto those surfaces. This can be as simple as laying down a tarp or using sheets to cover plants and such.

Once you’re prepped and the area is protected, it’s time to mix the dye. It doesn’t take a lot. You’ll need a sprayer and the dye you’d like, then you just follow instructions. Spraying isn’t much work, either. All you have to do is keep your nozzle about six inches above the mulch, then spray as you work your back and forth. Keep your distance even in order to keep your color even.


Now that we’ve learned about most of the different types of mulch, the million-dollar question yet remains: Which mulch is the best mulch? You may as wonder where to use mulch. As with our previous discussions, this is complicated, but only because there are so many options which can work, and each comes with its own benefits and downfalls.


For the best results, you have to think of keeping weeds out of your garden and landscaping as a team effort. First applying a layer of either cardboard, newspaper or fabric works to keep light from getting to the soil itself, thus giving weeds the opportunity to thrive. No light means no weeds, in theory.

On top of that, an organic mulch is a great way to go. Using something like a hardwood or bark mulch helps with the moisture and such, as a good mulch should, but being organic, it’s more likely to invite critters to live inside it. These critters have the potential to skitter about and eat any weed seeds which may find their way into the mulch or soil. It takes a village to keep weeds out.


First and foremost, if you’re going to have mulch around the walls of your house, make sure it isn’t wood. Wood mulch just loves bringing in bugs of all varieties, which can end up in your home, if they’re too close. Most of the bugs which show up are just minor nuisances, but one, in particular, can have devastating effects on your home: termites.

Termites love wood, of course, so it would make sense they would be attracted to wood mulches. To combat this, stick to the non-wood organics, such as leaf mulch, or go the full inorganic route. Lava rocks make a great addition to landscaping around the home, especially if they are a contrasting color to the home itself. Using the right sort of mulch can make a home stand out, increasing its curb appeal dramatically.


Deep mulch gardening, sometimes called sheet mulching, is almost like the Ronco of mulching, you can set it and forget it. Pick a spot in your yard in which you want to plant something and start piling on the materials. We’re talking pretty much anything organic you can think of. Straw, leaves, manure, cardboard, newspaper, whatever you have lying around which you don’t need and which started out as a plant.

The goal is to get it something like a foot tall, so it can work its mulch magic on the ground below. Deep-mulch gardening has the special ability to rejuvenate ground which has been compacted and may not be suitable for growing. By using this method, the ground begins to soften, and it leaches many nutrients from the mulch used on top.

Because of this goal, your best bet is to go with any sort of mulch, but the easier it is to break down, the better. You’re just going to need a whole lot of it, seeing as you want your pile to be about a foot tall. This is likely going to be the most difficult part. You can get out there and break up the ground a few times with the right tools, but finding enough material to get a foot of material over whichever size plot you intend to use can be something of a pain. Still, it’s worth it if you can work it out.


This is a topic which has bugged me for years. What’s the difference between compost and mulch? Without ever having looked into it myself, I never quite understood, but they’re two completely different beasts which can work together to create the perfect garden.

Compost is material teeming with bacteria and such after having been allowed to decompose in a controlled environment. Many people will use grass trimmings, manure and garbage to make it, often having allowed it to decompose in a bin or large pile in the yard.

Compost is typically mixed into the soil, giving it additional nutrients and such to help plants grow better than they may have with just using the soil. It can also be spread across the top of the soil as a mulch. Mulch, on the other hand, is only for the top of the soil and doesn’t necessarily serve to enhance the soil, so much as protect it.

Mulch keeps the soil at a good temperature, keeps weeds from growing, conserves water and generally looks nice. Compost doesn’t do any of that, it just makes the soil work better than it may have before. It isn’t a fertilizer, necessarily, though it does offer great nutrient-saving effects.

Mulch can also serve as this, to a degree, once it begins to decompose. This, of course, only applies to organic mulches such as bark, hardwood and leaf mulches, as opposed to any of the rubber or stone variety. When they decompose, they put their own nutrients into the ground, though still not to the extent of compost.

To have a truly remarkable gardening experience, make use of both compost and mulch, as these two go hand in hand to keep plants look fantastic and growing to new heights.


I think it would be more prudent to find out why somebody wouldn’t mulch, rather than why someone should. The benefits of mulching are myriad, ranging from healthier soil with greater plant growth to simply looking fantastic. Whether your goal is to have a better harvest or to have the best yard on the block, mulch is the way to go in pretty much any situation.

With all the varieties out there, finding one which suits your situation perfectly can be a breeze. Many have similar properties, but each also has something the others do not. You can be environmentally friendly, you can do it all on your own, and you can do it for cheap, all while working to make your yard the envy of anyone who may see it.


Though the benefits are obvious, perhaps the downsides are not. Frankly, the benefits greatly outweigh any negatives, but they’re worth noting. Mulch provides a great home for bugs. This, as mentioned, can be good in some respects. They can eat at weed seeds to keep weeds from dealing with your plants. However, other bugs may find their way to your plant and start munching it up.

While some mulches help retain heat, others keep it from getting too deep into the ground. This is positive and a negative. While it can keep flowers from blooming early, it can also force them to bloom late, which isn’t usually a good thing.

The moisture-retaining properties of mulch can also be negative. Yes, keeping the ground moist is a great thing. Plants love it. Plants don’t love too much water, though, as it can begin to cause issues. If extraneous water is not allowed to evaporate, it can sit and begin to start causing the plant’s roots to rot, or allow for fungus to begin to form. These are bad things if you couldn’t tell.

Finally, there is the issue of blocking light. This is great for stopping weeds from growing, but if you’re attempting to plant something new, you’re going to need some of that light to get down into the soil in order to help the seeds germinate. No germination, no plant, no garden.


Mulch is a great thing. Even with its downsides, it’s far more beneficial than other things you can do in your garden. Having mulch should, in theory, keep your plants grow stronger, your soil staying moister and weeds from growing and causing you problems.

In fact, mulch could potentially keep you from working more by maintaining proper soil health. All you’ll have to do with mulch is go out and rake it around every once in a while, and maybe replace it every few years, depending on the type you use.

All in all, don’t be afraid of mulch and don’t be afraid of what it can do to your garden. So long as you take care of it, mulch is going to be the greatest thing you can do to your landscape. What did you think of this list? Did it help answer any questions you had about mulch? If so, or if you had any further questions, please comment and share below!

*You might also like: Liquid Lawn Fertilizer vs. Granular: Which is the Best for Your Lawn?


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What’s the Purpose of Mulch?

The sun is shining in Texas, and for many that’s an invitation to get out into the garden, start barbecuing, or just lounge on the patio. When enjoying your outdoor space often you see the tree, shrubs, and flowers, but like many you probably take your mulch for granted—you do have mulch, don’t you?

Mulch is a vital tool in the smart property owner’s toolbox. It serves several purposes. Namely:

  1. As a Weed Barrier: Mulch blocks the light and suffocates weeds.
  2. For Moisture Retention: By blocking the light, mulch helps your soil retain more moisture so you have to water less often.
  3. As a Finishing Touch: Mulch adds a clean, decorative touch to your yard, helping boost curb appeal (and your home’s perceived value).

Mulch is just as varied as the plants in your yard, ranging from recycled to man made. Mulch can be made out of recycled rubber, straw, wood chips, glass, and rocks. Wood chips tend to be the most common and can be stained or left natural depending on the look you want to achieve.

Wood based mulch also comes in untreated and treated forms. Untreated means it was simply mulched and resold. Treated means it went through a heated process to kill off any weeds, insects, or diseases living on the mulched limbs. Most free mulches offered by municipalities are untreated. Because they’re untreated they often bring unwanted weeds and diseases into your flowerbeds. To be safe, always default to treated mulch. It doesn’t do you any good to bring in a product that causes the same problems it’s supposed to prevent.

Depending on the type of mulch you use, it can wash away over time, so be sure to replenish it so you can keep a 3” layer. Avoid doing too much or you can suffocate your plants for nitrogen and other valuable nutrients. When in doubt ask your nursery professional or lawn care pro for tips on mulch choice and application.

Get the Most From Vegetable Garden Mulches

Leaves gathered in the fall make fine mulch, too, although black walnut leaves should be avoided because they leach chemicals that inhibit the growth of tomatoes and many other plants. All leaves are easier to handle and more likely to enhance plant growth if you run over them with a mower once or twice before gathering them up. If you don’t have a bagger but do have a mower that will spew cuttings off to one side, you can quickly make piles of chopped leaves by mowing in concentric circles and directing the shredded leaves toward the center of the circle.

In my garden, I especially like the way long-vined squash behave if given a summer mulch of leaves over newspaper, so I go ahead and pile leaves on or near next year’s squash row in the fall. Indeed, any vacant veggie bed makes a fine winter holding place for leaf mulch. The pile will suppress cool-season weeds and attract earthworms, which are always more numerous under mulch.

Still, I need more mulch! As the public mulch supply has become less trustworthy (because of killer compost), I’ve stopped buying hay. Instead, I find myself growing more plants specifically to turn them into vegetable garden mulch. Twice a summer, I cut back waist-high comfrey plants that grow along a half-shaded fence. Persistent yet non-spreading, comfrey produces lots of big leaves that can be used to mulch beneath peppers, tomatoes and even sweet corn. An added bonus: Between cuttings, comfrey’s blue blooms attract lots of pollinators.

Other options for growing mulchable vegetation include maintaining a plot of tall perennial clover that can be cut with a scythe, or including dedicated, double-cropped, mulch-producing plants in your garden rotation plans. Based on biomass crop-production research conducted in 2006 at Iowa State University, you could try the idea of growing a winter-hardy grain from fall to spring (rye, triticale or wheat) followed by sorghum or a sorghum/Sudan grass hybrid during the summer. (In climates with mild winters you could use crimson clover or oats for the winter crop.)

Either way, you’ll come away with a cool-season mulch crop to harvest in early summer — just when you need lots of fresh, clean mulch. Another mulch crop will come along during the growing season’s second half, with another in time for mulching beds in fall and winter. (Sorghum regrows if cut back by half its size.) Winter-killed sorghum plants will mulch the soil through winter. In spring, you can turn under or gather up and compost the remaining sorghum skeletons and rotate the bed back to vegetables.

Other parts of your landscape can be tweaked to produce more mulch, too. As long as you avoid invasive species, large ornamental grasses can produce several armloads of straw when they are pruned back in late winter. Top choices include giant miscanthus (Miscanthus x giganteus) and ‘Karl Foerster’ feather reed grass. Growing seed-sterile varieties of giant miscanthus (maiden grass), researchers at the University of Illinois achieved double the straw yield typical of switch grass, a popular native grass grown for hay. When I cut back my big clump of maiden grass in late winter (a pruning saw works well for this), I usually get enough “hay” to mulch a 2-by-20-foot row.

The Thick and Thin of Mulching

Organic mulches cool the soil, which is great if you live where summers are hot. In Texas, 4 inches of organic mulch is recommended for top performance from tomatoes, peppers and other summer vegetables. But in climates with short, cool summers, a thick mulch can become a slug haven that keeps the soil cold and clammy.

The solution? Thin sheets of black plastic film mulch. Numerous studies have shown that black plastic film mulch improves the performance of many plants by warming the soil, while also keeping it moist and free of weeds.


For several years, I’ve experimented with two alternatives to black plastic film mulch: roll-out paper mulches and cornstarch-based biodegradable plastic films. A double thickness of biodegradable black film gave decent weed control, but I didn’t like seeing bits and pieces of it leftover in the soil the following season. Left bare or topped with organic mulch, I can’t say that biodegradable plastic films or roll-out paper mulches showed noticeable advantages over old newspaper.

In some situations, the use of black or colored plastic mulch, which runs $12 or so for a 4-by-20-foot piece, may be worth the trouble and cost. Colored plastic film mulches are only as thick as lightweight garbage bags, so they usually can’t be reused. The special single-season uses for colored plastic films are summarized in “Colored Plastic Mulches: A Rainbow of Benefits,” below.

Mulch First, Dig Later

Many research studies have compared how crops respond to organic materials used as a surface mulch versus mixing the same materials into the soil. Vegetable crops vary in how they respond to the direct incorporation of leaves, wood chips, yard waste compost and other organic materials into the soil, but yields are almost always better if organic materials have been applied as mulches than when the fresh materials have been mixed into the soil. So, when in doubt about how to use any organic material to enhance plant growth while enriching soil, first try applying it as mulch.

Colored Plastic Mulches: A Rainbow of Benefits

Colored plastic film mulches offer special benefits unique to their hues. If you don’t have these needs, organic mulches may do a better job in the long run. Organic gardening standards allow the use of plastic films as long as they are gathered up at the end of the season.

Black. Controls weeds and warms the soil beneath by up to 7 degrees Fahrenheit. Black film mulches work best where summers are mild. While more expensive, black plastic landscape fabric allows water to pass through it, and can be reused for several seasons.

Brown. Works like black mulch, but looks better in the garden and may also be available as reusable fabric.

Red. Reflects far-red rays from sunlight back onto plants, which can improve production of tomatoes by 10 to 30 percent.

Green. Can improve the performance of squash, melons and watermelons in climates with cool summers.

Silver. Confuses thrips and makes flea beetles nervous, so can be useful where either pest needs better management, especially in warm climates.

White. Controls weeds without warming the soil, so it makes a good substitute for black plastic in climates with hot summers.

Clear. Warms the soil for early spring planting more so than black plastic does, but doesn’t do as good a job at controlling weeds as the black plastic.

Contributing editor Barbara Pleasant gardens in southwest Virginia, where she grows vegetables, herbs, fruits, flowers and a few lucky chickens. Contact Barbara by visiting her website or finding her on Google+.

Why Mulch? 7 Benefits of Mulching

Mulching is one of the best things you can do for your garden. This is the act of placing a protective barrier (mulch) around your plants and over your bare soil. This protective barrier can be made up of a variety of decomposing organic materials, including bark or wood chips (from various tree species), pine needles, straw, and cocoa bean shells, or non- decomposing, non-organic materials such as black plastic, landscaping fabric, recycled tires, pebbles, and river rock. Here are seven of the biggest advantages of mulching.

1. Controls Weeds

Through the use of mulch you can limit the amount of weeds that spring up in the open spaces of your garden. The mulch acts as a barrier, limiting the amount of sunlight that can find its way to the weeds.

2. Retains Moisture

Organic mulches absorb water. Organic and non-organic varieties both cover the soil and limit evaporation. Retaining moisture, especially during hot, dry seasons can not only help out your plants, but it can also help out your water bill.

3. Prevents Soil Erosion

Mulching not only keeps existing water trapped in the soil, it also keeps rain water from washing away your soil. It does this by breaking the fall of the water and therefore lessening the force when the water impacts the ground.

4. Maintains Soil Nutrients

No only does mulch keep soil nutrients from being washed away with the rain, but it also can release nutrients into the soil if you are using an organic material. This happens as the organic material slowly decomposes on top of the soil.

5. Controls Pests

Using certain types of mulch, such as cedar bark, can deter certain pests due to the fact that the cedar bark has natural oils that act as insect repellant. To reap the full benefits, be sure to find a mulch that is very fragrant, as it will have the greatest affect on insects. But be warned, some mulches can encourage insects to flock to your garden and sometimes your house, so be sure to research which type of mulch will best suit your needs.

TIP: Our expert gardening advisor, Kathy Bosin suggests, “When adding mulch to your garden beds, avoid piling mulch up against the trunk or stems of plants. This can lead to insect and disease issues. Using too deep a layer of mulch can also be a problem — generally, 2 to 4 inches of mulch is recommended for most plants.”

6. Encourages Earthworms to Move In

Using organic material for mulching can encourage earthworms to occupy your garden soil. And as any good gardener will tell you, earthworms help improve soil structure and nutrient cycling.

7. Polishes up Your Garden

Mulch can give a garden a finished look by filling in the empty spaces while being one of the easiest fillers to maintain. Grass, groundcovers, and other fillers may take extensive care, such as mowing and watering, as well as competing for resources with your garden plants. Mulch is easy to care for and never competes with your other plants.

TIP: Kathy adds, “Mulching around trees not only promotes a healthy growing environment, but it also helps to keep maintenance equipment such as weed whips far from the trunk of the tree.”

Mulch or mulching are protective covers that extend over the ground to modify mainly the effects of the weather, usually at the beginning of each vegetative season. There are a variety of materials depending on the effect you want to achieve.

Mulch is a very beneficial technique that we should not stop practicing in our garden or organic garden . Mulching has a multitude of important functions, such as maintaining soil moisture, reducing the sudden changes in temperature that affect the roots, favoring microbial activity and other highly beneficial living beings such as earthworms, increasing the fertility of the earth, etc.

The mulch is applied around the stem of the plant or tree, leaving a distance between them of about 15 cm, it should be avoided that the mulch has direct contact with the stem or branches. If you use drip irrigation, first place the irrigation systems and then place the mulch on top.

In general, with a layer of about 3 to 6 cm of padding is enough to get to take advantage of all its benefits. The quilting with loose materials such as straw or hay can be slightly deeper, up to about 8 cm, or can also be added successively during the life of the plant.

Keep in mind that during the spring, excess moisture and keeping the soil cooler can reduce the chances of germination of the seeds, so it is usually not advisable to use mulch until the seedling measures about 15 cm.

Wood-based mulches such as sawdust or chips once decomposing can interfere with nutrients causing plants with more discrete growth than usual. To avoid this, you only have to add nitrogen previously to the soil or plant nitrogen plants .

Other materials that we can use for mulch or mulch are food shells, branches and leaves and even algae.

Table of Contents

Advantages of mulching

Protect from frost
Mulch protects plants against frost and extreme temperatures in winter. The plants are very sensitive to cold, so when the frost starts a good mulch can prevent the roots from freezing and dying.

Reduces evaporation
Padding reduces evaporation of water in summer. It retains the humidity of the soil accumulated during the spring rains that help to hydrate the plant. In this way we will not need to water them so much.

Avoid weeds
Avoid the proliferation of weeds, since it prevents the passage of light.

It serves as fertilizer.
If organic materials are used, they nourish the soil little by little while they decompose.

Protects from erosion
Protects the soil from erosion by rain and wind while maintaining the soil structure.

Less probability of rotting of aerial fruits when not being in contact with soil moisture

Less soil compaction

Roots develop more laterally and superficially on land taking advantage of all the space they have in the soil

Roots are more numerous by the microclimate generated under the padding

More effectiveness and safety in the use of fungicides, fertilizers or other products either natural or chemicals , but that is placed on the ground. This is in case of PLASTIC padding

Saving water Less water evaporation so we don’t need to water more regularly

Provides organic matter when the material of the mulch is integrated into the soil. In the case of leaf mulch, straw,

Eliminates the risk of cracking or breaking the soil (which damages the roots) ….. in all types of mulch

Disadvantages of mulching

Cost of mulching depend on the method you use can be costly.

You need to know the correct use of the padding according to the purpose you want to achieve

Attraction of some types of pests, according to the type of padding . The one that attracted the most was dry twigs and straw .

The mulching of dry leaves, can facilitate the presence of spiders and mites.

Disappearance of beneficial plants such as trebol , especially in the case of plastic mulch.

In the case of straw mulch : It cannot be stacked, nor can it be known in the case of drip irrigation, when some of the irrigation outlets do not work

In the pumpkins and zucchini, the hot humidity creates under the propitious plastic padding powdery mildew

In some types of mulch, such as that of straw, when it is fresh, it can germinate its seeds and become weeds

The mulch of herbs, leaves, or straw can attract rodents.

In the case of dry leaf mulch, the wind can cause great loss of the material, when this is not well settled.

Advantages and disadvantages of some materials for mulch or mulch


Advantages can be very cheap or free, it is very good for vegetables because it retains moisture superbly, biodegrades quickly improving soil structure, helps stop some pests and serves as a habitat for beneficial insects.

Disadvantages> can kill nitrogen and may contain seeds of unwanted plants. It usually attracts snails and rodents.

Gravel and small stones

Advantages> is an inert material that lasts for a long time. It can be very good in gardens and orchards because we can combine the different colors and textures that there are. It is a good choice for perennials.

Disadvantages> is not a good option for plants that need more acidic soils, in addition, during the hot months it can reflect sunlight and cause temperature increase.


Advantages> are free, they put about 5 or 6 sheets under another layer of padding of another material.

Disadvantages> aesthetically they are not very attractive and ink can be a problem

Cut grass

Advantages> are free, rich in nitrogen and they look pretty good.

Disadvantages> may contain seeds of unwanted plants, waste, residues of pesticides or synthetic fertilizers, etc.


Advantages> another free or very cheap option with easy access. They keep the humidity of the soil very well and avoid the appearance of spontaneous or uncultivated plants.

Disadvantages> It decomposes quickly if it compacts it can hinder the absorption of water, it can compromise the nitrogen reserves of the earth and acidifies the soil.

Corrugated cardboard

Advantage> is the best to avoid the appearance of unwanted or adventitious spontaneous plants (formerly called weeds).

Disadvantage> should not contain ink, staples or plastics attached. It can be unsophisticated.

Pieces of bark

Advantages> they integrate very well aesthetically both in gardens and in the garden. There are many different sizes to choose from, with the largest pieces being the ones that take the longest time to decompose and need to be replaced every many months.

Disadvantages> if you can not access the bark it can cost a lot, floats with abundant rains and can be transported to other areas, to prevent unwanted plants from growing, it is necessary to put another layer of mulch under the bark.

Crushed leaves

Advantages> are easily found, are free, attract earthworms and give a very beautiful appearance in orchards and gardens.

Disadvantages> are extremely light, so they are not a good option in areas with constant wind because they fly easily.


Advantage> can be easily obtained in forests, avoids the appearance of spontaneous herbs, lasts for a long time and aesthetically fits in gardens and orchards.

Disadvantage> if you can not get it from a nearby pine forest, buying it can be expensive and a lot of it is necessary to create a good mulch.

Wood chips

Advantages> can be obtained for free or very cheap and its duration is quite long.

Disadvantages> Some shavings may contain toxic chemicals that have been used to treat wood. If you notice a sour smell it is because the chips are decomposing anaerobically and produce alcohols that can harm the plants.


Advantages> is easy to handle, it looks great, adds more nutrients to the soil, improves moisture retention and can help prevent soil diseases to the plant.

Disadvantages> it is better to use it in small strategic areas or by applying only a thin layer under some other padding material.

Crushed tree bark

Advantages> this material lasts long, aesthetically it is good to use in vegetables, ornamental plants, shrubs, and trees.

Disadvantages> it is expensive and in the market, there are many imitations of wood stained with unhealthy chemicals.

How to Mulch a Flower Bed

Mulch is a useful addition to any garden or yard. Whether it’s organic or inorganic, mulch helps moderate soil temperature and weather damage, prevent weed growth, and retain soil moisture. Plus, a well-incorporated batch of mulch can totally transform the aesthetic of a garden or flower bed and give it a unique flair.

Mulching your garden or flower bed is an affordable and easy project, but if you’re new to mulching, you may have some questions about how to get the best results out of your efforts. These steps will help you understand the ins and outs of how to use mulch.

Step 1 – Choose a Mulch Type

For flower beds, organic mulches are typically better than inorganic ones. Organic mulches are composed of wood products, such as bark and branches, other plant material, or beans.

Organic mulches enrich the soil as they decompose and provide a welcoming habitat for earthworms and beneficial microorganisms. On the flip side, they can also attract pests like moles and rabbits.

Organic mulches come in a variety of consistencies. Mulches that are shredded 2-3 times are finer than single-shredded mulches and may be easier to spread and work with in a garden. Additionally, mulches may be aged up to several months in order to enhance the decomposition process. This provides additional nourishment to the soil. With that in mind, you will need to eventually replenish your mulch once it decomposes fully.

In very wet climates, organic mulch can hold too much moisture. This can attract snails and slugs, and potentially cause the stems of your plants to rot. If you have a problem with rodents, or live in a very moist climate, you may want to consider using an inorganic mulch, such as shredded rubber. The upside of inorganic mulch, is that it tends to have a longer lifespan.

Step 2 – Measure the Right Quantity

For a flower bed or similar areas of your garden, mulch should typically be between 2-4 inches thick. A layer of mulch that is too thin may not adequately protect your soil from weather damage and weeds, while a layer that is too thick may retain too much moisture and eventually lead to rot.

Your mulch amounts should also be calculated in accordance with your specific soil properties. Soils that tend to retain water will require less mulch than sandy soils. Additionally, mulch tends to settle and compact as it decomposes over time, so consider applying an additional inch or so of mulch to your soil after some time has passed.

Renew organic mulches every year or two as they break down. You can dig the old mulch into the garden soil to finish decomposing, or simply spread a new layer of mulch directly on top of the old.

Step 3 – Mulch Your Garden At the Best Time

If you are mulching a flowerbed, as opposed to a garden or whole yard, apply your mulch in the later parts of spring just before the weather turns warm.

Before applying mulch, carefully remove all weeds and roots from the garden. Just as mulch can supercharge your plants, it can also provide a great environment for weeds, so get them out of the way ahead of time.

If weeds are still a concern, put down a layer of five to seven sheets of newspaper before mulching to help cut the risk of weeds. Be sure to remove any labels from the paper. Labels could be problematic in your soil, but newspaper ink is soy-based, so it won’t add toxins to the soil as it decomposes, and in fact, instead adds organic material.

Be careful not to choke the flowers by covering them with mulch. Rather, leave a few inches of space around each flower or bush.

Step 4 – Source Your Mulch

Although store-bought mulch is high quality and tends to be relatively cheap, many gardeners and homeowners opt to create their own mulch. If this is your first time mulching, buying a pre-made mulch may be easier.

But moving forward, making mulch at home requires very little time and effort. You will need a garden shredder or chipper however. Homemade mulch is also an excellent way to clean up yard debris in an environmentally-friendly manner. Whether you choose homemade or commercial mulch, your garden will be healthier and more visually appealing if you plan carefully.

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