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How to Stop Grass From Growing in Mulch

By Faith McGee
Use pine needles for acid-loving plants or compost for alkaline plants.
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Grassy weeds are always one of the worst enemies for gardeners. Their vigorously growing root system can spread from lawns into flowerbeds. In addition, numerous types of grassy weed seeds can germinate inside the tiny crevasses in between organic mulch. You can tell the difference between grassy weeds and broadleaf weeds by examining their blades or stems. Grassy weeds have rounded stems, while broadleaf weeds are more colorful than grasses. It is essential to remove the grasses before they impede on the health of your plants.

Remove all of the mulch from the flowerbed. Grass seeds can be lurking inside the mulch, which will continue to create problems.

Dig up all grassy weeds. Press a shovel 3 inches away from the base of the weeds. Throw the weeds away or burn. Smooth out the surface and add dirt in areas that are uneven with a rake.

Lay down landscaping fabric. Cut X-shaped slits into the landscaping fabric to push over flowers and other ornamental plants.

Secure the landscaping fabric with pins. Landscape pins are U shaped and about 3 to 4 inches long. Press the pins through the fabric and into the ground around the perimeter of the flowerbed or every 2 feet. Press four pins in the middle to keep the fabric from moving around.

Spread 3 to 4 inches of fresh mulch over the landscaping fabric.


Things You Will Need

  • Shovel
  • Rake
  • Landscaping fabric
  • Scissors
  • Landscape pins
  • Mulch


  • Hand pull any grassy weeds that grow out of the new mulch.


  • Avoid spraying a herbicide around ornamental plants and seedlings to stop the grass, because the chemicals can kill the plants.