Landscape fabric is one of the most misunderstood products in the garden centre. Sold as a permanent weed solution, it works well in certain narrow applications and causes long-term problems in others. Understanding the difference will save you money, frustration, and a difficult remediation job years down the line.
What Landscape Fabric Is
Landscape fabric is a permeable woven or non-woven geotextile material designed to block light while allowing water and air to pass through to the soil below. It is distinct from plastic sheeting, which is impermeable and kills soil biology beneath it. It is sold in various weights — lighter for temporary use, heavier for permanent installation under gravel or stone paths.
Where It Works
Landscape fabric works well in two specific applications: under gravel paths and driveways, and as a base layer beneath decorative stone mulch in areas where no planting is intended. In these uses its job is purely mechanical — preventing gravel from sinking into the soil and suppressing weeds in a static, unplanted area. Under a 50mm layer of gravel, quality woven landscape fabric can be effective for ten or more years. It also has legitimate use as a temporary weed suppressant on bare ground before planting, as a six-to-twelve-month measure while plants establish.
Where It Fails
In planted borders and around trees and shrubs, landscape fabric is counterproductive within three to five years. Soil particles, wind-blown debris, and decaying organic matter accumulate on top of the fabric and form a growing medium above it — weeds germinate in this layer and their roots penetrate through the fabric, making them harder to pull than if there were no fabric at all. Meanwhile, the fabric restricts the earthworm activity and soil biology that plant roots depend on.
The Organic Mulch Alternative
For weed suppression in planted borders, a 75-100mm layer of wood chip mulch outperforms landscape fabric over the long term. Wood chips break down slowly, adding organic matter to the soil. Earthworms thrive beneath mulch and improve soil structure. Weed seeds that land on wood chip fail to germinate in significant numbers. The mulch needs topping up every one to two years.
FAQ
Can I use landscape fabric in a raised bed to keep weeds out?
Not recommended. Weeds in a raised bed almost always come from seeds, not from the soil below, so a bottom liner does not help. The fabric will interfere with root development and soil biology.
Does landscape fabric stop all weeds?
No — only weeds that would germinate in the soil below the fabric. Weeds that germinate in debris accumulated on top of the fabric are harder to remove than if there were no fabric at all.
How do I remove old landscape fabric that has been in place for years?
Cut it into manageable sections with a knife and pull each section up. Expect roots to have grown through it — they will need to be cut free. Remove all material including torn fragments.
Is biodegradable landscape fabric worth the extra cost?
For temporary use (covering bare soil before planting or between rows in a vegetable garden for one season), biodegradable fabric is a good choice. It breaks down in one to two seasons and does not need removing.
What weight of landscape fabric should I use under gravel paths?
A minimum of 100gsm woven polypropylene for foot traffic paths; 130gsm or heavier for areas with occasional vehicle access. Lighter products will puncture and fail within a few seasons under stone.
See also: Best Soil Mix for Raised Beds and Safest Materials for Edible Gardens.