One of the least glamourous materials in the landscape may be landscape fabric. It’s cheap, ugly, and is useful in a variety of applications. Our clients sometimes ask us about installing landscape fabric as a weed prevention tool, and we discourage this. Why you might ask? Because weeds can still grow in the areas it’s installed; it damages soil health; and the landscape fabric inevitably becomes exposed, creating an eyesore.
Primary sources of weeds are seeds that travel through the air, landing on the surface and then rooting down into the ground. While landscape fabric may make pulling these weeds easier because the plants won’t become deeply rooted, there nonetheless will be weeds. Landscape fabric in planting beds delays the surface-level mulch from decomposing and adding nutrients to the soil. It also acts as a barrier preventing beneficial soil critters (insects, worms, microbes, etc.) from moving nutrients through the soil and keeping soil structure loose and healthy for root growth. Finally, with just a few inches of mulch on top of the fabric, it becomes exposed over time and looks terrible.
What is landscape fabric good for, then? Well, as noted earlier, it’s great at keeping materials from mixing together. This makes it ideal for use under hardscapes such as paver patios, gravel pathways, dry creek beds, and drainage applications. Whenever we excavate for a hardscaped area, we apply landscape fabric directly on top of the soil before applying gravel or other rock. This prevents the rock from working its way back down into the earth. If you come across an undulating paver patio, it very well may be that landscape fabric was not installed, and the gravel above is migrating down into the soil. So, we use landscape fabric regularly – just not as a weed prevention tool.