Can I Spray 2, 4-D on Lawn? What Weeds it Kills + Mixing Ratio

2,4-Dichlorophenoxyacetic acid (2, 4-D) is a systemic herbicide that selectively kills broadleaf weeds. It is classified as an auxin-type herbicide because it causes cells in plant tissues that transport water and nutrients to grow endlessly. In other words, it destroys weeds by altering the way the cells of these plants grow.

Is 2, 4-D safe for lawns?

2,4-D is safe for lawns since herbicides containing it as the active ingredient do control most broadleaf weeds without harming the grass. You can spray it on your lawn in the right ratio to eliminate various non-grassy weeds, aka broadleaf weeds.

Caution should be taken, however, before spraying 2,4-D weed killers on turfgrass. Read the label to ensure that it is good for use on your particular turfgrass variety. Here’s the 2,4-D general factsheet for your reference.

Pro tip: I noticed Hi-Yield 2, 4-D is not labeled for use on St. Augustine grass. The product label cautions that the herbicide can cause injury to St. Augustine grass. If you plan to control broadleaf weeds using a selective herbicide on this type of grass, Trimec Southern Broadleaf Herbicide is a better option.

However, Trimec is also not labeled for use on Floratam, a variety of St. Augustine grass.

Most of the 2, 4-D weed killers are safe for use on Bermuda grass – a common Southern lawn grass. Be careful not to apply this herbicide to kill broadleaf weeds in dormant Bermuda grass or even during spring green up, and hot summer temperatures, as this grass is sensitive to this herbicide. It can destroy your lawn in its dormancy stage, usually around the month of January.

Best 2, 4-D Weed Killers

#1 MOST EFFECTIVE

Southern AG 2,4-D

Check Latest Price

#1 MOST EFFECTIVE

Southern AG 2,4-D

Check Latest Price

Affiliate links and images pulled from the Amazon Product Advertising API on: 2025-03-24

What weeds does 2, 4-D kill?

Not all lawn weeds can be killed using a 2, 4-D formula. Most products with 2,4-dichlorophenoxyacetic acid as the active ingredient are indicated to be used in non-crop areas to control weeds.

You can apply this broadleaf weed killer on lawns and on ornamental turf, driveways, patio areas, drainage ditch banks, and fence rows.

Here’s a list of weeds that 2, 4-D kills:

As you can see, the only grass that 2,4-D can kill is nutgrass. The rest is just a list of broadleaf weeds.

Does 2, 4-D Kill Crabgrass?

Crabgrass is a tough grass weed that keeps coming back if not controlled with a strong crabgrass pre-emergent and killer. 2,4-dichlorophenoxyacetic acid is indicated to kill broadleaf weeds, but not most grass weeds.

Therefore, 2,4-D will NOT KILL CRABGRASS. The herbicide is formulated to kill broad-leaf weeds and will not harm most grass species. Crabgrass is a species of grass and will not be affected when you spray 2,4-D to control weeds in your lawn.

If you have a crabgrass or a nutsedge problem in your lawn, you might want to try a strong grass weed killer for lawns to help you get rid of those grassy weeds. Most of the best weed killers that control crabgrass are non-selective, meaning they will harm any plant they come in contact with.

Therefore, for crabgrass control, ensure you use the spot-spray technique and follow it with overseeding to prevent having bare spots on your lawn.

A great crabgrass killer I recommend for killing crabgrass is the Drive XLR8 Herbicide. I’ve seen great results when trying to eliminate this grassy weed just by spot-treating the areas of infestation.

2, 4-D Mixing Ratio and Application Rate

Each brand of 2, 4-D herbicide comes with its own mixing ratio on the instruction label. The ratio and application rate depend on the concentration of the active ingredient in the herbicide.

In general, mix 2.5 oz of 2, 4-D weed killer (5 tablespoonfuls) with 1 gallon of water and use it to treat 400 square feet of weed-infested area in your yard. You can double the dose to 5oz per 2 gallons of water for treating 800 to 1000 square feet of weed-laden grass.

Note that this is not the exact mixing ratio for all 2, 4-D liquid herbicide brands. Always read the label for the recommended ratios and rate.

For example, Hi-Yield 2, 4-D mixing ratio for small areas:

• Use 3 to 4 fluid ounces (6 to 8 Tablespoons) per 1,000 square feet.
• Mix 1 – 3 gallons of water and apply uniformly over the area when weeds are small and growing actively before bud stage.
• The best time to apply is usually during spring and fall when the weeds are actively growing.

When to spray 2 4 d on the lawn

The best time to apply 2, 4-D weed killer on your lawn is when weeds are still young and starting to grow or growing actively.

This may be during spring, although some weeds germinate in fall and summer. Spray 2,4-D at least 6 weeks after newly seeding or sodding your lawn to prevent stunting the grass.

The timing for the specific day is also important. Ensure you apply this herbicide when the soil temperature in your lawn is below 90 F.

Take note that 2,4-D can also harm other plants such as flowers, so time the application on a non-windy day. This is to prevent the herbicide from spreading onto other plants and harming them.

But should you apply 2, 4-D before or after rain?

Most labels indicate that 2, 4-D is rainproof one hour after application. However, since most brands do not indicate on the label, it is safe to go with 6 to 8 hours of no rain. The ester in most of the herbicide formulations is rainproof within 1 hour. There are a few key differences between amines and ester herbicides.

It is important to use a fan-type nozzle when spraying 2,4-D.

FAQs on 2,4-D

Final Thoughts

2,4-D is an effective herbicide to kill broadleaf weeds but will not kill most grasses. This selective weed killer works quickly, somewhere between 24 to 48 hours after application but can be highly toxic to fish and other aquatic life.

References

• NPIC 2,4-D Fact Sheet
• Iowa State University Extension: Label Recommendations for Rain Delays with Postemergence Herbicides

You may also like…

• Best Weed Killer Sprays and Sprayers for Lawns
• What are the Best Backpack Sprayers? Reviews & Buyer’s Guide

Alex Kuritz( Founder, Writer )

Hi, Alex Kuritz here. Growing up I remember that my family had one of the best lawns in the neighborhood. Richly green and lush. I did a lot as I grew up in terms of caring and tending for not only my family’s lawn but also my neighbors. I can say I have years of experience, and I am here to share it with you.