Monday, May 5, 2008

Landscape - Landscape Fabric Problems

I have seen many issues in the landscape with the use of landscape fabrics. While they do have some limited applications and are a necessity in greenhouses and container nurseries, they can cause problems in landscape settings. The following is an article on the subject from Washington State University.

Increased concern over the use of herbicides has caused landscape professionals and consumers to look closely at non-chemical alternatives to weed control. Mulches are increasing in popularity as weed control strategies and have a number of additional benefits, including water retention and soil protection. Mulches may be organic, inorganic, or synthetic and often can bring an aesthetic quality in tandem with their principal role in plant health maintenance. Synthetic mulches, including geotextiles, are of interest to many consumers and professionals because they are perceived as nonbiodegradable, permanent solutions to weed control.

Initially developed for agricultural use, geotextiles have found their way into ornamental installations as landscape fabrics. These fabrics, a vast improvement over the impermeable black plastics still (unfortunately) used for weed control, are woven in such a way that water and gas exchange can occur but light penetration is significantly reduced. Hence, they are effective in reducing weed seed germination in areas where soil disturbance would otherwise induce germination of a horde of weeds. Such fabrics have been so effective in reducing weeds in vegetable and ornamental crop production that they have been applied to more permanent landscape installations.

The Reality

Like the perpetual dieter searching for a permanent weight loss pill, so we as landscape professionals and consumers continue to seek permanent weed control solutions. Unfortunately, there is no such permanent fix. We must remain “ever vigilant” in our battle with weeds and cannot rely on a product to do this passively. The fact is that weed control fabrics are not permanent and will decompose, especially when exposed to sunlight. Such fabrics are effective in agricultural situations, in annual planting beds, or where the landscape is regularly disturbed and the fabrics can be replaced when needed. For permanent landscapes, however, they are not a long term solution and in fact can hinder landscape plant health.

Some of the documented drawbacks of these fabrics are listed below.

• Geotextiles degrade in the landscape in as little as one year if unprotected from sunlight.
• Any organic matter or soil on top of the fabrics will hasten their colonization by weeds; this precludes covering the fabric with anything but inorganic mulch like pebbles. It also requires continual maintenance to keep the fabric free of debris.
• Weeds will eventually grow on top of and through these fabrics, making their removal difficult.
• Landscape plant roots can also colonize fabrics, and they are damaged when the fabrics are removed.
• The aesthetic quality of landscape fabrics is minimal; it becomes worse as the materials begin to degrade.

The Bottom Line
• Geotextiles are not effective weed control solutions for permanent landscapes
• Landscape fabrics used in permanent landscape installations will eventually become a high maintenance issue in terms of appearance, weed control, and landscape plant health
• Organic mulches are preferred alternatives for permanent landscape installations as they can be reapplied throughout the life of the landscape without damaging the existing plantings

Adapted from "The Myth of Landscape Fabric:Landscape fabric provides permanent weed control for ornamental landscapes" by Linda Chalker-Scott, Ph.D., Extension Horticulturist and Associate Professor, Puyallup Research and Extension Center, Washington State University. For more information, please visit Dr. Chalker-Scott’s web page at

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