cardboard to smother weeds and killgrass. This was a neglected bed overrun with weeds. I weed-whacked them down, covered in cardboard, and applied mulch. Use Cardboard or Newspaper to Smother Weeds - One Hundred Dollars a Month. I always feel a little excited at the first signs of spring—the trees start to get leaves, the grass gets green, and then the not-so-exciting part: weeds. Rather than cutting the sod or spraying harmful chemicals, you can use cardboard to kill the weeds and grass, with considerably less effort. Prepare the Site. 3. KillGrassWithCardboard. Photo: fotosearch.com.Simply cover the grasswithcardboard, overlapping the sheets as if they were shingles. Next, lay about four to six inches ofcompost or mulch over the cardboard. Water the area until it’s compacted. Using Cardboard to KillGrass.There are several natural ways to remove grass for a garden, including herbicides, solarizing, or using a sod cutter. Sheet mulching is more economical and it adds nutrients to the soil. How Long Does It Take Cardboard to KillGrass? Killinggrass while improving soil. Needs access to materials like cardboard or newspaper. 8. Mulching. Yes. 4–6 weeks. Grass removal with aesthetic cover. Requires a thick layer of mulch for effectiveness. Drench the cardboard with water. Add another layer of cardboard and soak it well.Top the straw with another ½- to 1-inch-thick pile of wet cardboard. This will help to hold everything in place for the next 4 to 8 weeks, as the pile smothers and kills the grass underneath. About Press Copyright Contact us Creators Advertise Developers Terms Privacy Policy & Safety How... KillGrasswithCardboard. fotosearch.com.Simply cover the grasswithcardboard, overlapping the sheets as if they were shingles. Next, lay about four to six inches of compost or mulch over the cardboard. Water the area until it’s compacted. I tried sheet mulching (killinggrasswithcardboard or newspaper) withcardboard in two different places at my house during the fall of 2022.