Things You'll Need
Killing existing weeds prior to laying sod increases the chances of the grass establishing itself and growing healthy. Garden weeds are unwanted annual or perennial plants that limit desirable plants from growing vigorously because of the strong competition they offer for soil moisture and nutrients. By killing all such weeds before laying sod, you clear the way for the new grass to grow and develop into a healthy and lush green. Depending on personal taste, use natural methods of killing the weeds or chemical alternatives.
Pour water in a long-spouted kettle and bring it to a boil. Wear gloves and carry the kettle outside to where the weeds exist. Position the tip of the spout directly over each plant and pour a steady steam of boiling water to cover it. The gush of boiling water burns the weeds, causing them to turn yellow and die. Rake to remove dead weeds, or repeat application everyday for stubborn or tenacious weeds until they die.
Pour horticultural vinegar over the undesirable plants to burn them. Unlike household vinegar, which contains 9 percent or more acetic acid, horticultural vinegar contains at least 20 percent acid and usually kills weeds in the first application. Pour the vinegar directly over each weed, ensuring complete coverage.
Create piles of 10 to 12 sheets of newspaper and spread these flat over the weeds to smother them. Overlap sides of adjacent piles to ensure complete coverage. The dense piles prevent sunlight, water and air from reaching the weeds below, causing them to become weak and straggly, and eventually die in four to six weeks. Weigh the newspapers down with wood chips to hold them in place in case of heavy winds.
Spray a glyphosate herbicide over the weeds to kill them in five to seven days. Pour the herbicide in a pump sprayer, and add the recommended amount of water specified on the label if it is in concentrated form.
Direct the nozzle over each weed and spray it to cover it evenly. The chemicals in the herbicide target the amino acids of the tissues in the weed plant and prevent them from carrying out routine functions, resulting in death.
Rake dead weeds from the soil and discard, or repeat application for tenacious weeds. You can also cut or clip tenacious weeds to assist the chemicals in penetrating internal tissues.
Pull out weeds by hand if there are a few in your area. Make sure you remove the complete plant, along with the roots.
Cover nearby desirable plants with a tarp to prevent spills from boiling water, vinegar or glyphosate.