Several types of weed mats are available commercially, some made of heavy plastic and some of fabric. Weed mats block out the sunlight to soil surrounding plants, trees or shrubs, killing weeds and preventing the weed seeds from germinating. Weed mats are effective, non-toxic alternatives to herbicides. Although plastic weed mats are usually less expensive than fabric, the fabric types are generally longer lasting, allow for sufficient water and air circulation and are safer for the environment.
Measure the area of your flower, shrub or plant bed, or other area where you intend to install the weed mat. Purchase the proper length and width of weed mat you need to cover the area, purchasing more than needed rather than less.
Remove all existing weeds from the area by hand-pulling or hoeing them. If you're using a weed mat made of plastic, poke some holes throughout the mat to allow water and air circulation.
Begin laying the weed mat, starting at one side of the plant bed and inserting a landscape staple to hold it in place. Stretch the weed mat across the bed area, up to the nearest existing plants.
Cut an X into the weed mat for each existing plant and carefully thread the plants through the hole in the weed mat. Stretch the weed mat while working your way in the same direction across the plant bed.
Stake the weed mat using landscaping staples around the entire plant bed border, inserting a staple every 12 inches or less. Trim off the excess weed mat around the plant bed border, ensuring that the edges of the mat extend to the border.
Trim the weed mat around the existing plants so that the mat doesn't cover the plant's roots. Cut an X or small hole into the weed mat where you're planting any seeds or new transplants.
Spread a 2- to 3-inch-thick layer of bark mulch over the weed mat to help hold it in place. The mulch will also help to reduce sunlight exposure to the weed mat, which will extend its lifespan.