How to Control Grassy Lawn Weeds


Grassy weeds can be a major problem in the lawn. Identification of grassy weeds, as opposed to the grass you wish to have in your lawn, can be difficult. Looking for grass blades that are a different shape or color than the rest of your lawn helps narrow down what are weeds and what is turf. Once identified, application of pre-emergence and post-emergence herbicides, as well as proper cultivation practices, will control and eliminate grassy weeds from your garden.

Step 1

Mow your grass so that the blades are between 2 and 3 inches long. This helps increase grass coverage, as well as the effectiveness of any herbicide sprays.

Step 2

Rake the lawn with a dethatching rake to break up the thin layer of dead grass that lays on the yard before applying herbicides. This increases the herbicide's ability to penetrate the soil.

Step 3

Apply your pre-emergence herbicide using your sprayer directly into the soil. Spray on a day where the wind is low and there is little chance of rain. Pre-emergence herbicides prevent the roots of the weed from growing properly and are usually selective, affecting only weeds in the lawn.

Step 4

Spray any full-grown weeds in the lawn using a post-emergence herbicide in your herbicide sprayer. Apply this herbicide directly to the plant, making sure not to allow herbicide drift because many post-emergence herbicides are nonselective and may affect the grass of your lawn.

Tips and Warnings

  • Always wear gloves and protective eye wear when handling and applying herbicides.

Things You'll Need

  • Mower
  • Dethatching equipment
  • Pre-emergence herbicide
  • Sprayer
  • Post-emergence herbicide


  • Colorado State University Extension: Control of Annual Grassy Weeds in Lawns
  • Purdue University: Identification and Control of Perennial Grassy Weeds
  • Oklahoma State University: Controlling Grassy Weeds in Lawns
Keywords: grassy lawn weeds, grass weed control, lawn weed control

About this Author

Cleveland Van Cecil is a freelancer writer specializing in technology. He has been a freelance writer for three years and has published extensively on, writing articles on subjects as diverse as boat motors and hydroponic gardening. Van Cecil has a Bachelor of Arts in liberal arts from Baldwin-Wallace College.