There are safe and environmentally friendly ways to kill unwanted grass in your yard. It isn't always necessary to use chemicals that can harm the soil or the animals that live in the environment. Not only is it safer to use items from around your house, it is also more affordable.
Mow the area of grass that you would like to kill as short as you are able. This will enable the sheets of plastic or paper to lay flat to the ground.
Lay down a thick sheet of dark plastic on the area of grass. You may also lay down layers of newspaper in the area as well. If you are using newspaper, overlap the newspaper in several different directions and then wet it down to keep it from blowing away.
Cover the newspaper or plastic with mulch. Spread the mulch over the entire covered area of grass. If you have covered the grassy area with plastic, put down large stones to hold the plastic in its place.
Keep the layers of newspaper or sheet of plastic in place for a couple of weeks. The covered area will block out the sunlight, killing the grass. It may take longer to kill larger areas of grass.
Remove the newspaper or plastic once the grass has died. You may then dig or till up the old grass to prep the area for planting or gardening.