How to Get Rid of Crabgrass Without Killing Your Lawn
If you’ve noticed patches of coarse, fast-growing grass taking over your yard, there’s a good chance you’re dealing with crabgrass.
The frustrating thing about crabgrass is that it spreads quickly and can make an otherwise healthy lawn look thin, patchy, and neglected. The good news is that you can get rid of crabgrass without damaging your lawn if you use the right products and timing.
In this guide, we’ll cover how to identify crabgrass, the best ways to kill it, and how to prevent it from coming back next season.
What Is Crabgrass?
Crabgrass is an annual grassy weed that thrives in thin, stressed lawns. It typically begins germinating in spring when soil temperatures warm up and continues spreading throughout the summer.
Unlike your regular lawn grass, crabgrass grows in wide clumps and sends out stems that spread outward from a central point, giving it a crab-like appearance.
Because it grows aggressively, it often crowds out desirable grass and leaves bare spots once it dies in the fall.
How to Identify Crabgrass
Common signs include:
- Wide, spreading growth pattern
- Light green color compared to surrounding grass
- Thick stems that radiate outward
- Rapid growth during hot weather
- Large clumps forming in thin areas of the lawn
If you’re seeing these symptoms, the sooner you treat it, the easier it will be to control.
The Best Way to Kill Existing Crabgrass
One of the most effective post-emergent treatments for crabgrass is Quinclorac.
Quinclorac specifically targets crabgrass while being safe for most established lawns when used according to label directions.
Recommended Product
Quinclorac 75 DF (Check Amazon)
Benefits:
- Kills existing crabgrass
- Works on young and mature crabgrass
- Safe for many common lawn types
- Can be mixed in a pump sprayer for targeted treatment
Use a Non-Ionic Surfactant for Better Results
Many homeowners skip this step and wonder why their weed killer doesn’t work as well as expected.
A surfactant helps the herbicide stick to the leaves and improves absorption.
Recommended Product
Southern Ag Surfactant for Herbicides (Check Amazon)
Benefits:
- Improves herbicide effectiveness
- Helps spray stick to waxy weed surfaces
- Often increases control rates
Apply With a Quality Pump Sprayer
A good sprayer helps ensure even coverage and reduces wasted product.
Recommended Product
2-Gallon Pump Sprayer (Check Amazon)
Benefits:
- Easy spot treatment
- Adjustable spray patterns
- Ideal for lawn weeds
When Should You Spray Crabgrass?
For best results:
- Spray when temperatures are below 85°F if possible
- Avoid windy days
- Do not mow for 2-3 days before treatment
- Allow the product to dry completely
- Avoid rain for at least 24 hours after application
Most homeowners begin seeing results within one to three weeks depending on the maturity of the crabgrass.
How to Prevent Crabgrass Next Year
Killing existing crabgrass is only half the battle.
The real secret is preventing new seeds from germinating.
Apply a Pre-Emergent
Pre-emergent herbicides create a barrier that stops crabgrass seeds from sprouting.
Recommended Product
Prodiamine Pre-Emergent Herbicide (Check Anazon)
Benefits:
- Long-lasting prevention
- Helps stop new crabgrass growth
- One of the most popular pre-emergent options
Keep Your Lawn Thick and Healthy
Crabgrass thrives in weak lawns.
A dense lawn naturally crowds out weeds and leaves little room for crabgrass to establish itself.
Focus on:
- Proper mowing height
- Consistent watering
- Seasonal fertilization
- Overseeding thin areas
- Correcting compacted soil
Recommended Product
Broadcast Lawn Spreader (Check Amazon)
Benefits:
- Even fertilizer application
- Great for seed and pre-emergent products
- Saves time on larger lawns
Common Mistakes Homeowners Make
Waiting Too Long
Mature crabgrass is much harder to kill than young plants.
Skipping the Surfactant
Many herbicides perform significantly better when paired with a surfactant.
Ignoring Bare Spots
Thin areas become prime locations for future crabgrass infestations.
Skipping Pre-Emergent
Without prevention, new seeds will simply germinate next season.
Final Thoughts
Crabgrass can quickly take over a lawn, but it doesn’t have to be permanent.
For existing crabgrass, a Quinclorac-based herbicide combined with a quality surfactant is one of the most effective solutions. To keep crabgrass from returning, apply a pre-emergent in spring and focus on maintaining a thick, healthy lawn.
A little prevention now can save you from fighting a much larger crabgrass problem next season.