Landscape fabric is usually installed underneath mulch during landscaping projects.
It does not matter whether the mulch material is gravel, wood chips, or bark mulch.
There is one main reason to install landscape fabric.
It separates the native soil from the mulch layer. In other words, it helps prevent weeds from growing up from the soil and also prevents seeds that blow in from taking root.
However, after some time, weeds will still appear even in areas where landscape fabric was installed.
If the area is left unmanaged, the mulch layer can break down much faster.
Because of this, some people say, “Mulch doesn’t really work.”
But despite this, using landscape fabric still has several benefits.
Benefits of Using Landscape Fabric
Weed control becomes easier.
It becomes easier — not completely weed-free. Some weeds will still grow, but the amount is usually much smaller and easier to manage.
It is relatively inexpensive.
Compared to other landscaping options such as paving stones, concrete, or artificial turf, mulch installation is usually much more affordable.
It keeps soil and mulch separate.
Landscape fabric prevents mulch materials from mixing into the soil over time.
How to Make Mulch Last Longer
Rather than disadvantages, the more important question is how to maintain the mulch so it lasts longer.
Mulch must be thick enough.
The mulch layer should be at least 3 inches thick.
If the layer is too thin, the landscape fabric becomes exposed to sunlight, rain, and physical damage. Over time it will tear or develop holes.
Some mulch materials shrink over time.
Stone mulch such as limestone, crushed rock, or river rock can last a long time.
But organic mulch such as wood chips or bark mulch gradually decomposes and becomes compacted. This reduces the volume and may expose the fabric underneath.
From time to time, adding more mulch helps protect the fabric and extend its life.
Use professional-grade landscape fabric.
Thin fabric tends to break down much faster.
Thicker, professional-grade fabric lasts significantly longer.
Remove weeds as soon as they appear.
Even though only a small number of seeds will successfully grow, weeds can still appear. When they do, it is best to remove them immediately.
If weeds are left to grow, they will produce more seeds. Over time, the number of weeds can increase significantly. Their roots become thicker, and fallen leaves create organic matter that helps future seeds germinate more easily.
If neglected for too long, the area may eventually require a complete replacement of the landscape fabric.
Replacing mulch later becomes more difficult.
Once landscape fabric has been installed, redoing the mulch area later can be more difficult than the original installation. For this reason, it is important to do the job properly the first time.
How Long Does Landscape Fabric Last?
Depending on how well it is maintained, landscape fabric mulch will eventually break down.
Some installations last 3–4 years, while others can last 10 years or longer.
The lifespan can also depend on the surrounding environment. For example:
- nearby weed fields
- nearby lawns
- areas with heavy leaf fall
Despite its limitations, the biggest advantage of landscape fabric mulch is still cost efficiency compared with other weed-control options.
With proper maintenance, it can make garden weed management much easier for many years.
Considering that it can reduce weed problems for 3 to 10 years or more, many homeowners still find it to be a worthwhile solution.
Written by Andy Lee
Owner of Andy’s Landscape Inc. – Landscape Contractor in Maple Ridge, BC