What Crabgrass looks like
Thick clumps of coarse, yellowish-green grass growing in a star pattern, much coarser than your lawn grass.
Photo: Wikimedia Commons
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Best approach: Herbicide spray
Hand-pulling is possible for small patches but crabgrass drops seeds easily, making herbicide the better long-term strategy. Pre-emergent in spring is the gold standard.
Best products for Crabgrass
Formulated to kill crabgrass without wiping out your grass — see the timing and chemistry below.
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Dimension 2EW (Dithiopyr)
✓ Kills crabgrassLiquid concentrate; 64 oz half gallon; mix with water and spray
Scotts Turf Builder Triple Action1
✓ Kills crabgrassBeginner friendlyPrevents crabgrass for up to 4 months, kills dandelion, clover and other listed broadleaf weeds, and feeds. Apply to wet grass, no more than twice a year. Not for St. Augustine. Its label allows centipede, but centipede does better with a stand-alone weed killer and a lighter feeding.
Scotts Halts Crabgrass & Grassy Weed Preventer
✓ Kills crabgrassBeginner friendlyHow much do you need?
Herbicide is dosed by lawn size. Pick your yard size for a quick estimate:
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When to treat Crabgrass
Apply pre-emergent in early spring, before soil reaches 55°F — once it sprouts, prevention is off the table for the year.
Chemical treatment
Apply a pre-emergent herbicide (containing dithiopyr or pendimethalin) in early spring, 2–4 weeks before soil temperature hits 55°F consistently. If crabgrass already appeared, use a post-emergent (quinclorac) in spring while plants are young.
Non-chemical management
Mow at 3+ inches to shade soil and prevent germination. Maintain dense turf through fall overseeding.
How to stop Crabgrass coming back
Maintain thick, healthy turf through proper mowing height and watering—crabgrass thrives in thin, stressed lawns.
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Measure my lawn — it's free →FAQ
What does Crabgrass look like?
Thick clumps of coarse, yellowish-green grass growing in a star pattern, much coarser than your lawn grass.
What's the best way to kill Crabgrass?
Herbicide spray. Hand-pulling is possible for small patches but crabgrass drops seeds easily, making herbicide the better long-term strategy. Pre-emergent in spring is the gold standard.
Is Crabgrass hard to get rid of?
Crabgrass is rated moderate to control. Consistent treatment over a season usually does the job.
How do I stop Crabgrass coming back?
Maintain thick, healthy turf through proper mowing height and watering—crabgrass thrives in thin, stressed lawns.
Other grassy weeds
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