Landscape fabric stops weeds and lets water through
Landscape fabric is a woven or non-woven material that sits between your soil and the ground below. It blocks weeds from pushing up through the bottom and sides of your raised bed while still letting water and air move through. You install it before you fill the bed with soil, and it typically lasts two to five years depending on sun exposure and the fabric weight you choose.
The fabric does not prevent weeds from blowing seeds onto the top of your soil — you still weed the surface. What it stops is the perennial weeds already in the ground underneath from sending roots up into your bed. Without it, you will spend the season pulling bindweed, quackgrass, and other deep-rooted plants that are nearly impossible to remove once they are tangled in your vegetables.
Heavier fabric (often labeled 3 ounces or higher) lasts longer and blocks more aggressive weeds, but costs more and is harder to cut and install. Lighter fabric (1 to 2 ounces) is cheaper and easier to work with, but may tear during installation or degrade faster in direct sun. For most home gardens, 2-ounce fabric is a practical middle ground.
Key Takeaways
- Measure your raised bed's length, width, and height, then buy fabric large enough to cover the bottom and extend 6 to 12 inches up the sides.
- Lay the fabric flat in the empty bed, smooth out wrinkles, and find it to the top edge with landscape staples or wood screws and washers every 12 inches.
- Cut an X through the fabric at each corner so it folds neatly up the sides without bunching.
- Overlap seams by at least 6 inches if your bed is wider than the fabric roll, and staple the overlap to keep it from shifting.
- Fill the bed with soil after the fabric is secured; the weight of the soil holds it down further.
Measure your bed and buy the right amount of fabric
Start by measuring the inside length and width of your raised bed. Then measure the height of the bed walls. You need enough fabric to cover the bottom and extend up all four sides by at least 6 inches — more if you want to fold it over the top edge and find it there.
The math is straightforward: add twice the height to both the length and width. If your bed is 4 feet long, 2 feet wide, and 12 inches tall, you need fabric that is at least 6 feet long (4 + 1 + 1) and 4 feet wide (2 + 1 + 1). Landscape fabric typically comes in rolls 3 to 4 feet wide, so a 4-foot-wide bed will require two pieces with an overlap, or a custom-cut section if your supplier offers it.
Buy a little extra — it is cheaper to have leftover fabric than to run short and have to piece together scraps. Most garden centers and online suppliers sell landscape fabric by the linear foot or in pre-cut rolls.
Lay the fabric flat and smooth out wrinkles
Empty your raised bed completely so you are working with bare ground or the bottom surface. Unroll the landscape fabric and lay it flat across the bottom, starting at one corner. Smooth it out with your hands as you go, working toward the opposite corner. Wrinkles trap air pockets that can shift when you add soil, leaving gaps where weeds can push through.
If you are using two pieces of fabric to cover the width, overlap them by at least 6 inches in the middle of the bed. Smooth both pieces so they lie flat against each other. You will staple this overlap once the fabric is secured to the edges.
Take your time here — five minutes of smoothing now saves you from pulling weeds through gaps later in the season.
Cut the corners and fold the fabric up the sides
Once the bottom is smooth, fold the fabric up one side of the bed. At each corner, you will have excess fabric that bunches. Cut a small X through the fabric at the corner — about 2 to 3 inches across — so the two flaps can fold up the adjacent sides without overlapping. This keeps the corners neat and prevents the fabric from wrinkling as it goes up the walls.
Fold the fabric up all four sides so it extends 6 to 12 inches above the top edge of the bed. If your bed is tall or you want extra protection, fold it all the way over the top and down the outside — this is optional but does prevent weeds from creeping in at the rim.
find the fabric to the top edge with staples or screws
Once the fabric is folded up and smooth, fasten it to the top edge of the bed so it does not shift when you add soil. The two most common methods are landscape staples (U-shaped pins about 6 inches long) and wood screws with large washers.
Landscape staples are faster and do not require a drill. Drive them through the fabric into the top edge of the bed frame every 12 inches around the perimeter. Push them in firmly so they sit flush with the wood — a staple that sticks up will catch on your shovel or hoe later.
Screws and washers work better if your bed frame is composite or if you want a more permanent installation. Drill a pilot hole through the fabric and into the frame, then drive a 2-inch wood screw through a large washer and into the hole. The washer spreads the load and keeps the screw from pulling through the fabric. Space these every 12 to 18 inches.
Overlap and staple seams if you used two pieces
If you laid two pieces of fabric side by side, staple the overlapping section to hold it in place. Drive staples through both layers every 6 to 8 inches along the overlap. This keeps the seam from separating when you add soil or when water pressure builds up during heavy rain.
Check that the overlap is smooth and flat before you staple — any wrinkles in the seam will become weak points where weeds can work their way through.
Fill the bed with soil and plant
Once the fabric is secured, fill your raised bed with soil. The weight of the soil holds the fabric down and keeps it from shifting. As you fill, the fabric will settle and conform to the shape of the bed. You do not need to do anything else — the fabric stays in place under the soil.
When you plant, you can cut small X-shaped slits through the fabric where you want to place transplants or seeds. The slits are small enough that weeds still cannot push through the surrounding fabric. For direct seeding, you can plant directly into the soil without cutting — the roots will find their way through the fabric, and the fabric will not interfere with germination.
Frequently Asked Questions
Do I need landscape fabric if I already have a weed barrier underneath my raised bed?
If the ground below is already covered with cardboard, newspaper, or plastic, you still benefit from fabric inside the bed. The ground barrier stops deep-rooted perennials, but the fabric inside protects your soil from contact with whatever is below and makes it easier to replace the bottom layer later without disturbing your plants.
Can I use plastic sheeting instead of landscape fabric?
Plastic blocks weeds but also blocks water and air. Your soil will stay waterlogged and roots may rot. Landscape fabric is designed to let water drain while blocking weeds — plastic does only half the job. Use fabric, not plastic.
What do I do if the fabric tears during installation?
Small tears (under 2 inches) are not a problem — weeds cannot push through a small hole. For larger tears, patch the area with a scrap of fabric laid over the tear and stapled down, or cut out the damaged section and overlap a new piece by at least 6 inches on all sides.
How often do I need to replace the landscape fabric?
Heavier fabric lasts four to five years; lighter fabric may last two to three years. Sun exposure and foot traffic speed up degradation. When the fabric starts to break apart or tears easily, it is time to replace it. You can pull out the old fabric and lay new fabric without emptying the bed.
Should I use landscape fabric if I am growing root vegetables like carrots or potatoes?
Yes. The fabric does not stop roots from growing down through it — they push right through. The fabric only blocks weeds from growing up. Your carrots and potatoes will grow normally, and you will have fewer weeds to pull.