How To Kill Weeds In The Lawn But Not The Grass

It isn’t a death sentence for the grass if you have weeds in your yard. There are ways to kill weeds in the lawn without killing the grass, and they aren’t all chemical options.

Pre-emergent herbicides

Apply a pre-emergent herbicide as a preventative in late winter or early spring before soil temperatures warm up and trigger weed seed germination. These products don’t kill the seeds before germination, but instead, they interrupt growth processes to prevent the seed from progressing all the way through germination.

Post-emergent selective herbicides

Post-emergent selective herbicides are applied when the weeds are actively growing and are generally safe for lawn applications since they target broadleaf or non-grassy weeds. They may begin to work overnight but typically take up to two weeks to see the full results. These herbicides kill down to the root, preventing the weed from resprouting.

2, 4-D is a selective chemical herbicide commonly applied to turf to control non-grassy weeds. Most turf varieties are resistant to the herbicide’s active ingredient, 2,4-Dichlorophenoxyacetic acid, so 2,4-D won’t kill the grass, just the weeds.

Manual Weed Removal

Pulling weeds by hand is another effective, albeit time-consuming, way to kill weeds without harming the grass. The best way to pull them is to use a flathead screwdriver or a unique weed popper tool designed to remove weeds down to the roots. Remember that if you snap the stem and the roots survive, the weed will regrow quickly.

Keep Lawn Healthy

Keeping your grass healthy and robust is the best way to eradicate weeds in your lawn. When grass thrives and creates a thick canopy, it will shade out the weeds and out-compete them for resources.

  • Fertilize your lawn on a schedule recommended for your local climate and type of grass, including a late fall application.
  • Only water your grass when it needs moisture to prevent over-watering.
  • Water infrequently but deeply, providing more water every few days, instead of watering a little daily.
  • Routinely aerate or dethatch your lawn to improve the movement of air, water, and nutrients through the thatch layer on the soil surface and down into the root zone.
  • Never remove more than one-third of the blade height when mowing, and always mow grass to the recommended height.
  • Overseed every spring and fall to fill in bare patches.
  • Regularly scout for insect and disease problems, treating them as soon as they are discovered.