It is depressing to look at your lawn and see it full of weeds or bare patches. Or, you may want to start a garden but do not want to dig up the stubborn grass in your lawn. Killing your grass with plastic is an organic, easy method that is slow but does not involve backbreaking labor. This method can also improve the soil. The solarization that occurs when you cover grass with plastic will also help kill problematic soil fungi and nematodes. This method is a good alternative to chemical weed killers.
Decide how much area of the lawn to kill. Are you killing the grass to redo the lawn or do you just want to start a small garden? Plan carefully and map out the area so you don’t end up killing more grass than you want to.
Measure the area where the grass will be killed. This will help you buy the right amount of plastic.
Purchase heavy plastic black or clear plastic. This will block out light in addition to smothering grass. Plastic about 1 or 2 ml thick will work best as it won’t reflect as much sun as the thicker plastics will.
Mow the grass you want to kill and cut it very close. Set your lawnmower blade to the shortest available height.
Level the area. Rake it and remove any large rocks or dirt clods.
Water the soil. Make sure it is damp but not soaking. The wet soil will conduct heat better than dry soil.
Cover area with plastic. Anchor the edges with rocks or soil.
Leave the plastic on for one to two months in the spring or summer. In the fall or winter, leave it on for up to three months.