How long landscape fabric lasts depends on what you put on top of it. Exposed fabric can fall apart in as little as 1 year. Fabric buried under gravel can hold up for 15 or more years. The covering you choose matters just as much as the fabric grade itself.
I pulled up a section of fabric from one of my beds after five years and compared it to a fresh roll. When I first saw it, the old piece had faded from black to dull gray. It tore like wet paper when I tugged on it. Roots from nearby shrubs had poked through hundreds of small holes. The edges had curled up where mulch washed away, and those bare spots crumbled between my fingers. The new fabric from the same brand felt three times as tough by comparison.
Three forces break your fabric down over time. UV rays from the sun hit first. They crack the polymer chains in the polypropylene and make it brittle. Next, decomposed mulch and dirt clog the pores shut. Once clogged, the fabric stops draining water and stops blocking weeds. A new growing layer forms right on top of it. Third, plant roots push through weak spots and tear the weave from below. All three of these forces speed up when you skip the covering layer.
Dr. Linda Chalker-Scott at WSU found that fabric can break down in as little as one year without sun protection. Penn State Extension studied fabric that sat in the ground for 20 years. They described it as soggy and rotten with zero strength left. That old fabric needed a huge effort to pull out of the beds.
Your landscape fabric lifespan also varies by the grade you buy. Cheap fabric under 2 ounces per square yard may only last 1 to 3 years in a garden bed. Mid-grade fabric in the 3-ounce range can hold up for 5 to 8 years with mulch on top. Commercial-grade woven fabric at 4 to 5 ounces per square yard goes 15 or more years under stone. The aggregate shields it from every force that breaks fabric down.
Your weed barrier durability depends on the cover you pick. Gravel and stone give the best shield. They block UV light and don't break down into pore-clogging particles. Wood mulch ranks second but you need to refresh it every 1 to 2 years as it thins out. Leaving fabric with no cover at all gives you the worst outcome no matter what grade you bought.
Cover your fabric with at least 2 to 3 inches (5 to 7.6 centimeters) of material right after you install it. Check it once a year by pulling back mulch in a few spots. Look for tears, fading, or roots poking through. Set a reminder to replace cheap fabric in your beds every 3 years so you're not caught off guard. Quality fabric under stone can last your whole time in a house without a single swap. I tested this approach with a gravel side path and the fabric still looks like new after eight years under the stone.
Read the full article: Landscape Fabric: Pros, Cons, and Uses
