Newspaper Mulch

• 1). Mulch the old grass to smother and kill it before seeding. Starting from a corner of the grassy area, spread a pile composed of 10 to 12 sheets of newspapers over old grass.
  
  
• 2). Overlap the edges of adjacent piles by 3 inches to prevent sunlight or moisture from seeping through to the grass below. Continue laying piles until you cover all the old grass over the area. Extend the edges of newspaper piles by several inches.
  
  
• 3). Mist the newspaper piles lightly so they stay in place and do not shift in case of high winds.
  
  
• 4). Cover the newspapers with a 3-inch-thick layer of organic mulch. Mulching serves a twofold purpose: it weighs the newspapers down to keep them in place and presses the grass plants closer to the ground, smothering them more effectively.
  
  
• 5). Rake and discard dead grass when it dies, which usually takes four to six weeks.
  
  

Boiling Water

• 1). Pour water in a kettle and bring it to a boil.
  
  
• 2). Hold the kettle's handle with an oven mitt and immediately take it outside to where the old grass is growing.
  
  
• 3). Pour boiling water over the old grass plants to burn them. Direct the flow of water from the kettle's spout above each plant and pour to douse it completely. The stream of boiling water kills the plants, causing them to turn yellow.
  
  
• 4). Rake dead grass plants or remove from the soil with a trowel and discard.
  
  

Herbicide

• 1). Measure the width and length of the area where the old grass exists. Multiply the dimensions to determine the square footage, so you know how much weed killer to use. Ideally, you need 1 gallon of weed killer for every 300 square feet of space.
  
  
• 2). Pour glyphosate herbicide in a pump sprayer. Follow label directions to add water to the concentrate, if necessary.
  
  
• 3). Spray the herbicide over patches of old grass. Start from one corner of the area and work your way to the other to prevent missing any grass plants. Direct the spray from the nozzle directly over each plant, covering it completely before moving on the next.
  
  
• 4). Inspect the grass after two to four days for signs of browning and wilting. Repeat application over stubborn plants.
  
  
• 5). Rake dead grass plants and discard.