How To Kill Crabgrass, If you only have a few crabgrass plants in your lawn, you can treat them with a ready-to-use product like Scotts® Spot Weed Control - For Lawns. This spray kills listed weeds, including crabgrass, down to the root without harming your lawn, when used as directed.,
For a safe alternative to glyphosate or other harsh herbicides, you can also spot-treat crabgrass patches with a natural weed killer, such as Earth's Ally Weed and Grass Killer, made with sea salt, vinegar and soap. This solution is safe for use around children and pets.
Boiling water always works as a weed killer. The hot water will instantly kill any plant life it touches. You can use a sprayer got better control. You can cover the dying crabgrass with compost or compost/soil combination.
Apply a postemergent herbicide, such as fluazifop or quinclorac, to crabgrass patches to control crabgrass that has already germinated. Postemergent herbicides work best when applied to young crabgrass that still only has two to five leaves.
Mature crabgrass contains forked seed heads holding thousands of tiny seeds that will scatter on the newly created open soil patch. Leave these seed heads alone, but young closed seed heads are okay to pull out.28-Apr-2016
The university found that spraying crabgrass with 5 percent acetic acid vinegar killed crabgrass and kept it away for up to 13 weeks. Vinegar has little effect on roots because they generally don't absorb acetic acid. Vinegar is nonselective and will kill desirable turfgrass as well.14-Dec-2018
Actively growing crabgrass in your lawn calls for selective, post-emergent herbicides, such as Image All-In-One Lawn Weed Killer or Image Herbicide Kills Crabgrass, that kill crabgrass and leave your lawn grass untouched.