Use and installation of landscaping fabrics

By Melanie Mathieson
Gardening Guru

Landscape fabrics can help eliminate weed growth around trees, shrubs and plants for years, when laid done before the application of an organic mulch, saving the time and energy you’ll spend weeding and spraying herbicides. Landscape fabrics are woven, non-woven or spun-bonded synthetic petroleum products that, when laid on the ground around plantings, they provide a physical barrier against weeds and tree roots. Using a barrier for weed prevention is not new, of course, but in the past the only product available for weed prevention was plastic mulch. Unlike plastic, landscape fabrics breathe, letting air and water through, and don’t adversely affect the health of plants. In fact, research has shown that trees, shrubs and plants with landscape fabrics around them grow just as well as ones without fabric, yet without the same weed competition.
The best place to use landscape fabrics is around trees and shrubs or under stairs, decks and patios where you don’t want weeds to grow. I don’t recommend using them for flower beds containing annuals and the have very limited used in a perennial flowerbed. The reason for this is because when planting and transplanting annual flowers, gardeners tend to make many holes which then allows weed to grow out from underneath the fabric. Also many perennial plants expand slowly allowing weeds to creep in around the base of the plant. Remember that landscape fabric is a tool to reduce weeds but it is not 100% guaranteed to prevent all weeds from growing. Even the best landscape products on the market have had tough perennial weeds such as, quack grass eventually make their way through the fabric. A few pieces of quack grass are still easier to pull out than a whole garden full of it so it is still recommended that you try a landscape fabric in your yard or garden.
There are many landscape fabric brands available to homeowners. The best brands for suppressing weed growth are the ones with the smallest-sized pores (spaces between the fabric fibres). Small pore spaces don’t allow weed or tree roots to penetrate and get a foothold in the fabric. If the manufacturer hasn’t indicated the spore space on the packaging, you can raise the different brands up to the light and see how much light shines through. The less light that penetrates, the smaller the pore spaces, and probably the less weed growth with that fabric. Landscape fabric is an investment for your garden, so do not buy the “cheap” brand and expect great results. Most brands on the market are now UV-stabilized and can last for more than five years, even in direct sun. Despite this it is still highly recommended that you cover the fabric with a mulch product of your choosing. The latest research in landscape fabrics is creating a new generation of treated fabrics that are even more effective in controlling weeds regardless of the types and depth of the mulch. An exciting product expecting to reach the marketplace in the next few years is a fabric that is a non-woven landscape fabric impregnated with copper. Whenever tree or weed roots come in contact with the copper, they’re essentially stunted, thus making the fabrics last even longer. The investment you put into a quality landscape fabric will reward you in the end with less labour for weeding over a longer time span. Better quality means a longer time before it has to be replaced.
When installing landscape fabrics, first clear the area of all existing weeds. When installing in a newly developed garden I suggest laying down the fabric across the expanse of the garden, with at least a six-inch overlap between pieces, and anchor the fabric with metal pins that you can make from pieces of coat hanger or other strong wire, cut and bent into a u-shape. Position your plants in their pots on top of the fabric until you are satisfied with the layout. Once ready to plant, cut an “X” shape in the fabric equal in length to the diameter of the pot for each plant. Do not cut away the flaps that the “X” cut makes. Push back the flaps and then dig a hole to accommodate the plant. Once correctly planted rearrange the flaps back down on the soil adjusting by folding around the plant. Only cut away excess is you really have to. Pin the flaps down once positioned. It is best to cut the holes and plant the plants one at a time in order to allow for adjustment of the fabric as you go. Once all plants are planted and the fabric is secure, you are now ready to cover with a mulch product. If you are putting the fabric down in a garden with established plants you will have to do a lot of cutting and overlapping around the established plants. Make sure that when installing the fabric that you bring it up around the base of the plant as best as you possibly can in order to reduce soil exposure allowing for weed growth. This can be quite labour intensive and frustrating so you may want to use newspapers instead.
The initial investment of time and labour can reward you with extra time to sit and enjoy your garden – weed free.