How to Kill Lawn Grass for a New Garden Site


It is often necessary to kill existing lawn grass when creating a garden bed or adding landscape features that enhance the appearance of the area. Depending on personal taste, use a chemical glyphosate herbicide to kill the grass, or adopt an environmentally safe method that involves spreading plastic over the grass to smother it (the process is called solarizing). The herbicide kills grass immediately, but is costly and leaves chemicals in the soil, preventing immediate planting. Soil solarizing, on the other hand, is inexpensive but takes up to three months or longer, depending on the size of the area.


Step 1

Mow the lawn grass as short as possible, using the lowest setting on a manual or powered lawn mower.

Step 2

Hammer stakes in the ground to demarcate the area that requires herbicide application. Extend twine around the stakes and wind securely. The twine also prevents foot traffic over dying grass.

Step 3

Wear long rubber gloves, a face mask and protective eyeglasses. Pour the herbicide into a pump sprayer. Starting at one end, spray close to the grass to ensure the blades are completely covered. Continue spraying the entire area until you reach the end.

Step 4

Remove protective gloves, face mask, eyeglasses and clothing. Wash your hands thoroughly to prevent chemicals from coming in contact with your skin, eyes, nose or mouth. The grass will begin to brown in four to five days. Repeat herbicide application over stubborn patches.

Soil Solarizing

Step 1

Mow the lawn grass as short as possible. Collect grass clippings in a collection bag and dispose appropriately.

Step 2

Till the soil to loosen it to a depth of 5 inches. Use a manual or power tiller and turn the grass along with the roots in the existing soil.

Step 3

Dig 4- to 5-inch trenches around the edges of the area you want to solarize, spaced equally apart. Use a shovel and collect the soil into a wheelbarrow. Douse the remaining soil with water from a garden hose until the moisture leaches down to a depth of 10 inches. This moisture conducts heat through the area, killing grass roots completely.

Step 4

Spread plastic sheets over the area, pressing them down to ensure maximum contact with the grass. Push the edges into each trench and pour the soil from the wheelbarrow over each to weigh it down so it remains in place. The plastic prevents air, water and sunlight from reaching the grass and traps the heat of the sun to kill grass roots and seeds.

Things You'll Need

  • Lawn mower
  • Hammer
  • Stakes
  • Twine
  • Rubber gloves
  • Face mask
  • Protective eyeglasses
  • Herbicide
  • Pump sprayer
  • Tiller
  • Shovel
  • Wheelbarrow
  • Plastic sheet


  • University of Illinois Extension: Stepping Stones to Perennial Garden Design
  • Colorado State University Extension: Preparing the New Garden Plot
  • Oregon State University Extension Service: Garden Hints
Keywords: new garden site, kill lawn grass, remove unwanted grass

About this Author

Tanya Khan is a freelance author and consultant, having written hundreds of thousands of words for various online and print sources. She has an MBA in Marketing but her passion lies in giving her words wings.