The Landscape Fabric Weed Barrier Myth

I’ve seen it again and again. Helping a friend renovate their garden, I dig down a few inches and my shovel becomes entangled in a sheet of black plastic or some other material, collectively known as landscape fabric. Oh boy. Another case of pie-in-the-sky magic weed barrier.

“What’s this?”, I ask.

“Weed barrier.”

“Really? Then why are there foot-tall weeds in your garden?”

landscape fabric with weeds

Landscape fabric is fine to use under walkways, but not in garden beds. It does little to suppress weeds after the first season and some fabrics seriously restrict air and water exchange.

One of the great gardening myths is that landscape fabric will suppress the weeds in your garden for years. Sold under many trade names and made from an assortment of materials varying from plastic films to renewable sources, weed barriers are also sometimes impregnated with herbicides and fertilizers.

An experienced gardener learns that weed barriers defy logic, strangle plants, and decimate soil. Weed seeds largely move by air or animal and are deposited in the mulch or organic material on top of the weed barrier – mulch which doesn’t decompose as it should because the weed barrier doesn’t allow it to contact the soil.

Now to be fair, landscape fabric has its uses. If you install a new annual garden every year, it’s great. As you’ll be pulling up every plant and replacing the fabric yearly, it will serve its purpose. It’s also useful in commercial agriculture. But it’s less than useless in perennial gardens and can actually do a lot of damage to your plants and soil.

Read more on the landscape fabric myth from Linda Chalker-Scott, Ph.D., Horticulturist and Associate Professor, Washington State University

 Browse on Amazon: Organic Lawn Care Products 

The facts about landscape fabric weed barriers

Weed barrier fabrics were developed for agricultural use, meant to be used for one season only. In fields, the fabric is placed on top of the soil and the plants are installed through them, with an ample cutout so the plant can receive enough water and fertilization. Nothing is placed on top of the fabric so that water, fertilization, air, and gas exchange can take place. The fabric is the mulch.

However, in home gardens, perennial plant roots, especially roots of large shrubs and trees, frequently become entangled in the fabric. I’ve seen it often during renovations – roots spread across the top of the fabric or become entwined in it, and not underneath it in the soil as they should (that pesky mother nature foils the best laid plans). The root systems of healthy trees and shrubs must grow at least as wide as their drip line, but weed barriers restrict this growth. The lack of deep penetrating roots make the tree or shrub easily toppled by high winds and very susceptible to drought.  These pics from the University of Florida Extension service illustrate how landscape fabric girdles tree roots.

Tough weeds most definitely will grow through these fabrics. Anyone who gardens where the mighty Canadian Thistle grows will agree – I’m convinced that thistle will grow through steel.

Landscape fabrics will suppress below-the-fabric weed seeds the first season, but airborne seeds which settle in organic mulch atop the fabric will germinate, and some will root. As the mulch level increases, and organic decomposition occurs, more opportunity for rooting of weed seeds exists. Grasses like Nutsedge are a real problem – it will easily push through the fabric and the “nuts” (tubers) which are attached to the roots are virtually impossible to remove when growing underneath the weed barrier. And if you don’t get the entire nutsedge out, you get more nutsedge.

Many of the old fabrics aren’t very permeable, if at all. I’ve frequently seen soil beneath and above these weed barriers dry as a bone and compacted hard as cement, the color of baked clay. The plants were starving for nutrients and struggling to find water, slowly dying, even with layers of compost and mulch on top. And with no water penetration, little soil food web activity takes place, which one notes immediately by a distinct lack of worms and insect life. Conversely, when used in very wet or soggy areas, the weed barrier can trap water beneath it, creating a swampy mess.

Weed barriers separate the soil from the mulch and don’t allow proper biological activity and drainage to take place. Mulch, compost, and anything else you place on top of the soil requires actual contact with the soil to properly decompose. No decomposition means no humic acids to feed the plants.

I never asked one, but earthworms HATE landscape fabric. Worms eat organic material, which they can’t reach through the fabric, and they can’t poke their heads above the soil for air. So they leave. I have yet to see more than a few stray worms in soil underneath these fabrics.

Aesthetically speaking, when the fabric is exposed, it looks just awful – horrendous, ghastly, dreadful. Did I mention how bad it looks when the mulch slides off?

Planting bulbs through landscape fabric is a pain. Animals which do their work below ground like gophers can sometimes push bulbs off your mark and if they do, there’s little chance that tulip is going to be able to push through the barrier in spring. And if you’re cutting holes in the weed barrier, you’re also allowing air, water and sunlight to get at weed seeds, so what’s the point?

Good luck dividing plants like geraniums and irises.

Bad landscapers plant shrubs and trees with landscape fabric wrapped around the rootball. I suppose they believe that the roots will grow through the material.  They’re wrong. Roots will wrap around themselves inside the material until the plant basically strangles itself.

So why do so many companies sell landscape fabric? Because it seems like such a good idea and so many home gardeners and bad landscapers keep buying it. Accept the fact that there is no magic weed barrier (say it out loud, it’s liberating). Any mulch applied heavily enough will do a far superior job to landscape fabric: stones, pea gravel, wood chips, or yard waste. Layer it 2-3″ thick, with black and white newspaper or corrugated cardboard beneath it, and very few weeds will get through it.

The best weed suppression is achieved by planting low-growing ground covers like yarrow, sedum, coreopsis, verbena, sage, juniper, bergenia, geranium, coral bells, phlox, vinca, or carpet bugle. Ground covers easily out-compete weeds in your garden and mature groundcovers also cut down on the expense of buying and hauling mulch every year.

Garden Tip: For those who have trouble bending to pull weeds, invest a few dollars in a stirrup-shaped hoe which will save your back and make weeding a breeze.

Read more: Why I Hate Landscape Fabric, from North Coast Gardening; Good pics which illustrate the problem are on the Tropical Embellishments blog.

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About Todd Heft

Todd Heft is an organic gardener and freelance garden writer who lives in the Lehigh Valley, PA and has gardened for most of his life. When he isn't writing or reading about organic gardening, he's gardening. His first book, "Homegrown Tomatoes: The Step-By-Step Guide to Growing Delicious Organic Tomatoes In Your Garden" is available on Amazon now. Google

17 Responses to The Landscape Fabric Weed Barrier Myth

  1. Kris Abrahamson says:

    I have always suspected weed cloth was bad for the soil. Thank you for providing the evidence.

  2. Hammo says:

    Yep, I hear ya!

    I’ve used plastic fabric in the past and the weeds just push through it. Also tried thick newspapers and the water wasn’t getting through.

    My best results have been through solar sterilization. I cover the area to be planted with a heavy black plastic, and let it bake in the sun for a few weeks.

    When I lift the plastic the weeds are dead and the weed seeds no longer germinate. Well at least 80% of them.

  3. Angelina says:

    Do you have any advice for my situation? When we bought our house we spent weeks ripping out invasive ivy that had covered 1/3 of our yard. We tried to rip out the roots as far as we could, however we have been made painfully aware that the ivy is still there hiding underground. I foolishly put raised garden beds in near where some ivy had been and found that the ivy had come up under the beds and literally filled every inch of them with roots, smothering all the plants in there. You could barely get a shovel through it. I was going to try putting a double layer of the thickest weed cloth on the bottoms of the beds and try again, but maybe that won’t keep the ivy out? Maybe I should move the beds somewhere else? Also, I’m wondering if I should get rid of the dirt that was in the beds- do you know if ivy can regenerate from little bits of root? And I won’t use chemical weed killer, even if the ivy drives me over the brink.

    • Todd Heft says:

      Angelina: Yes, Ivy can be quite persistent, as you’ve learned. Do not put weed barrier under the raised beds, as that may reduce the ability of the bed to drain after heavy rain, defeating the purpose of the bed. Yes, Ivy can regenerate from small bits of vine. yes, moving the beds is an excellent idea, but if you do so, fill them with new soil and compost. If you want to keep the beds where they are, try soaking them with a white vinegar solution to acidify the soil and discourage the ivy growth. However, you’ll have to wait a season before planting vegetables or most fruit, as they won’t do well in the acidified beds.

  4. April H says:

    I have used pro five landscape fabric on the hill behind my back yard. I live in the foothills of Northern Utah and am inundated with scrub oak. It grows horizontal toward the house to get to the sun light as the hill faces the southwest. I try to kill and cut down as much of the runners as possible, but it is just impossible to keep it out. The area is behind a rock wall and we like to keep it ‘natural.” I have used weed barrier cloth with quite a bit of success. I don’t want anything but the wild choke cherries, wild roses and the few pines that I have planted to grow. I put natural shredded mulch on top and it keeps the weeds and scrub oak from growing out of control. I think there is a place for weed barrier, but definitely not in your garden area where you have ornamentals.

  5. Michael says:

    Todd, we recently removed all the turf from our front yard and replaced it with drought tolerant native landscaping. Unfortunately, within a few weeks nearly our entire yard has been over run by yellow nut sedge and purslane. Our new garden has no weed fabric and lots of ground cover, yet the weeds have pushed out the desirable plants and killed most, if not all, of the ground cover. Given the severity of the situation, what other options do we have other than installing a weed barrier?

    • Todd Heft says:

      Michael: Renovating a garden or landscape always poses challenges like this. When we tear up existing plants and replace them with new, much smaller varieties, we leave lots of space for “weeds” to take over. Plus, during a massive planting like yours, we expose lots of weed seeds that never received light and water before. It takes some time, at least 2 seasons for the newly planted landscaping to establish itself and start growing and covering those “opportunities” for native weeds.
      First of all, you’ll need patience and elbow grease. A weed barrier is not the solution, as it will restrict the natural growth of the new plants and especially the ground covers, as they must attach directly to the soil. You’re going to have to be diligent for this season and next, and pull or otherwise remove weeds around your new plants. If your property is large, invest in a Stirrup Hoe like this one, which makes weeding a breeze – you just keep cutting the tops of the weeds off, little bending or kneeling required.
      Next season, and season by season, fewer weed seeds will be exposed to the elements, and as your new plants grow in, they’ll shade and cover more area. Eventually, they’ll be packed tight in there and few weeds will have the opportunity to sprout.
      Hang in there!

  6. Susan H. says:

    My question is how do you remove the black fabric ? We just moved into a house with landscape fabric laid in all of the beds around the house, and I can’t plant anything. Should we scrape all the mulch to one side, cut the fabric and pull it up, then re-mulch the beds? It’s very tough and hard to cut.

    • Todd Heft says:

      Susan: You have the right idea. Whatever is on top of the fabric has to be removed. If you’re keeping any of the plants in the bed, cut around them before pulling up the fabric and watch for roots that have become entangled in it. Work very carefully around the plants, because if they’re entwined in the fabric, you’ll have to work to free them from it. After you pull it up, I highly suggest adding a few inches of finished compost, because the plants are probably starving for nutrients, as is the soil. Then add mulch on top – the old stuff (if organic), or new if needed.

  7. John Selden says:

    “These pics from the University of Florida Extension service illustrate how landscape fabric girdles tree roots”

    No, they don’t—they demonstrate the desirability of removing synthetic burlap from the root balls of saplings before planting. See:

    A very different situation…

  8. I LOATHE the stuff! Especially since the former owners of our current house thought it’d be super fun to use double layers of it around the entire house/in every bed and then use ROCKS as mulch. Like, thousands of dollars worth of rocks. Of course they also thought astroturf glued to the front porch and steps was cool.
    (Anybody need some rocks?)

  9. One of the biggest barriers to organic gardening success, and I mean that literally, is landscape fabric. Any kind of fabric or plastic that keeps weeds down will also keep fallen leaves or mulch from adding organic matter to your soil, leaving behind a hardened, dead zone where plants struggle to survive.

  10. Ellen says:

    Great post! I’ve said this for years but my friends looked at me like I was crazy.

    • Erika M. says:

      Same with my mother, having spent all her life gardening she kept saying the same. My sister, being a proud young owner of a house and garden was trying to explain her these were the modern methods of gardening when my mom said it was bulls..t. Now she can herself that see mom has been right but you know how it is about mothers and kids – mothers cannot know better than landscapers. So, going to send this article to my sister 🙂

      • Todd Heft says:

        Erika: LOL. I know exactly what you mean. People sometimes just have to discover the basics of science through “empirical research”.