How to Get Rid of Crabgrass Without Killing Grass

You can get rid of crabgrass without killing your lawn, but the right method depends on timing. Before crabgrass emerges, use dense turf and correctly timed pre-emergent control. After crabgrass appears, pull small plants or use a selective post-emergent herbicide labeled for crabgrass and your grass type. In late summer, when crabgrass is mature and close to frost, it is often better to stop seed production, plan fall overseeding, and prevent next year’s crop.

Crabgrass is a warm-season annual. It germinates in spring and early summer, spreads during heat, produces seed from midsummer into fall, and dies with frost. The plant dies every year, but the seeds it leaves behind create next year’s problem.

If you have dogs, read Best Weed Killer Safe for Dogs before applying herbicide. If crabgrass is filling bare areas, use How to Fix Bare Spots in a Lawn Fast and When to Overseed Lawn. For the full seasonal plan, see DIY Lawn Care Schedule for Beginners.

Last updated: June 5, 2026.

Quick Answer

To kill crabgrass without killing grass, use selective control and correct timing. Prevent crabgrass by mowing at least about 3 inches where appropriate, watering deeply instead of lightly every day, filling thin turf, and applying a labeled pre-emergent in spring before crabgrass germinates. For visible young crabgrass, hand-pull small patches or spot-treat with a selective post-emergent labeled for crabgrass and your turf species. Do not use nonselective weed killers in the lawn unless you are willing to kill the grass they contact.

Confirm It Is Crabgrass

Crabgrass is often confused with other grassy weeds. It usually has a lighter green color than turfgrass, grows low and spreading, and can form a coarse, open clump. Large crabgrass may have hairy leaf blades and sheaths; smooth crabgrass is less hairy.

Crabgrass is most common in:

sunny thin turf
lawns mowed too short
areas watered lightly and frequently
compacted soil
edges near driveways and sidewalks
late spring seedings with open soil
bare spots left after disease or insect damage

If the plant is a sedge, quackgrass, tall fescue clump, orchardgrass, or dallisgrass, crabgrass products may not work.

Why Crabgrass Comes Back

Crabgrass wins where the desirable lawn is weak. It thrives in heat and open soil. It does not compete well in dense shade or dense, properly mowed turf.

The long-term fix is not just killing this year’s plants. It is preventing seed and closing the openings.

Key prevention:

mow high enough
avoid scalping
water deeply and less often
aerate compacted areas
overseed thin cool-season lawns in fall
repair bare spots
fertilize based on grass type and timing

For a complete lawn program, see DIY Lawn Care Schedule for Beginners.

Best Nonchemical Control

Hand-pulling works when crabgrass is young and scattered.

Best time to pull:

after rain or irrigation
before seedheads form
when plants are small

Use a weeding tool to remove the crown and roots. Fill the hole with soil and seed if it leaves a bare spot. A bare hole can become another weed site.

Hand-pulling mature crabgrass can be frustrating because the plant sprawls and may have rooted nodes. At that point, preventing seed and planning fall repair may matter more.

Pre-Emergent Control

Pre-emergent herbicides are applied before crabgrass emerges. They create a control zone near the soil surface that affects germinating seedlings.

Common homeowner active ingredients include:

prodiamine
pendimethalin
dithiopyr
bensulide in some products

Timing is critical. University guidance commonly uses soil temperatures around 55 degrees F as a spring cue, but local timing varies. Apply too early and protection may fade. Apply too late and crabgrass may already be up.

Many pre-emergents must be watered in according to the label. If you plan to seed grass in spring, be careful: many pre-emergents also prevent desirable grass seed from establishing.

Post-Emergent Control

Post-emergent herbicides target crabgrass after it appears. They work best on young plants. Mature crabgrass is harder to control.

Common professional or homeowner active ingredients may include:

quinclorac
fenoxaprop
mesotrione
topramezone in some professional-use products
dithiopyr for very young crabgrass in some products

The product must be labeled for:

crabgrass
your lawn grass species
your site
your application timing

Some products can injure certain turf species or newly seeded lawns. Heat and drought stress can increase injury risk. Always read the label before applying.

What Not to Use on Lawn Crabgrass

Do not spray nonselective weed killer such as glyphosate or high-strength vinegar on crabgrass growing inside a lawn unless you accept that desirable grass can be damaged or killed too.

Nonselective products are useful for:

driveway cracks
gravel
full lawn renovation
edges where grass loss is acceptable

They are not the right tool for spot-treating crabgrass inside a lawn you want to preserve.

What If Crabgrass Is Everywhere?

If the lawn is mostly crabgrass by late summer, killing every plant immediately may leave bare soil and a weed seedbed. In cool-season lawns, a better plan is often:

Mow before seedheads mature where practical.
Avoid spreading seedheads around unnecessarily.
Core-aerate if compacted.
Overseed in late summer or early fall.
Fertilize correctly for the desired grass.
Apply pre-emergent next spring if compatible with your seeding plan.

Read When to Overseed Lawn before deciding on herbicide timing.

Crabgrass and New Grass Seed

This is where many homeowners make an expensive mistake. Spring seeding and crabgrass prevention often conflict because many pre-emergent herbicides stop grass seed too.

Options:

Seed cool-season lawns in fall instead of spring.
Use a product specifically labeled for use with new seed if appropriate.
Spot-treat after seedlings have matured enough per label.
Repair small bare spots manually and prevent crabgrass later.

If your seed failed, read Why New Grass Seed Is Not Growing.

Mistakes to Avoid

Mowing short to “stress” crabgrass.
Watering lightly every day.
Applying pre-emergent after crabgrass is already mature.
Using nonselective spray in the lawn.
Applying herbicide during heat or drought stress against label directions.
Seeding immediately after a product that prevents germination.
Treating without identifying the weed.
Letting mature crabgrass go to seed.

FAQ

Will crabgrass die in winter?

Yes. Crabgrass is an annual and dies with frost. The problem is the seed it produces before it dies.

Can I overseed after killing crabgrass?

Often yes, but the waiting period depends on the herbicide. Read the label. Some products require a waiting period before seeding.

Does mowing high really help?

Yes. Taller, dense turf shades the soil surface and reduces crabgrass germination. University of Minnesota notes raising mowing height to at least 3 inches helps reduce crabgrass seed germination.

Is crabgrass preventer the same as weed killer?

Pre-emergent crabgrass preventer stops seedlings before emergence. Post-emergent weed killer targets visible plants. They are different tools.