Is Landscape Fabric Necessary?

Many people ask if they need landscaping fabric when they start a landscape project, or just after landscape fabric has been installed either by themselves or a professional. In a word, the answer is "no," but we'll look at why it is installed, why it is not necessary, and what could be used instead.

Landscape fabric is generally put down as a weed barrier around new plants such as shrubs or flowers, to protect their fragile root systems until they are well established and no longer need the protection. Some kind of mulch, such as bark chips or gravel, is usually placed on top of the fabric to make it look "natural." Theoretically, the weed barrier should be removed once the plants are established and can fend for themselves. However, ask yourself when is the last time you saw a landscaper removing weed barrier from previous projects. The answer is probably never.

The problem with using landscaping fabric as a weed barrier is that it doesn’t allow nutrients and sometimes water to get to the plants you are trying to grow. Even if you are placing it under decorative rock, within a year or two it will start to fray and degrade, and the weeds will come through anyway, as noted by the University of Arkansas Division of Agriculture. Given the expense of most landscaping fabrics, this amounts to money and time wasted, which most people can’t afford. In the meantime, you are also starving the soil underneath of nutrients, and making it ripe for weeds that don’t need as many nutrients as cultivated plants.

The best weed barrier is a good, natural mulch such as untreated bark or shredded leaves and twigs, or other thriving cultivated plants to out-compete the weeds. A thick mat of leaves will effectively block anything trying to grow under it and according to OrganicGardening.com, they will biodegrade to feed your soil at the same time. For really stubborn weed patches, try applying a thick layer of pine needles, or duff, as the acid content in them will prevent most anything from growing. Just beware that over time, this may change the pH of the soil in that area to be more acidic than most shrubs and flowers can handle.

The only reason to use landscaping fabric is for temporary purposes, such as when you are trying to kill existing weeds or grass in a certain area, in order to plant something else there the next spring or fall. However, even in those cases, a roll of black or clear plastic from the hardware store is much less expensive and does a better job of killing the plant life beneath it. If it’s meant to be "permanent," such as under decorative rock, just be aware that it will have to be replaced every few years.

Many professional landscapers still use it because their customers demand it-- they want new landscaping to be weed-free from the get-go with no hassles. However, 3 to 12 months later, that fabric may be tearing or completely ineffective. As with everything else, do your research and don’t be afraid to speak up when something seems too expensive or unnecessary.