When To Apply 2,4-D To Your Lawn

Our grass is growing strong and healthy! Then again, so are a few weeds. How can we get rid of the weeds without harming the grass?

A lot of people turn to 2,4-D as a reliable weed killer that can be applied to grass. What is 2,4-D, anyway, and what is the best way to use it?

What is 2,4-D herbicide?

2,4-Dichlorophenoxyacetic acid, or what we commonly call 2,4-D, is a selective herbicide. This means that it wreaks havoc on broadleaf weeds, but your grass should be mostly unaffected.

On Sale
Southern Ag Amine 2,4-D WEED KILLER, 32oz - Quart
  • Low, economical use rate of 1 to 4 pints per acre
  • Controls many broadleaf weeds & woody plants
  • Use in turf, pastures, rangeland, ditch banks, fences…

How it works

2,4-D is absorbed through the leaves of the weed. The compound imitates a plant growth hormone called auxin. Growth hormones for weeds? You would think that would not harm the weed, but it does!

Once the weed absorbs 2,4-D, the plant goes into uncontrollable growth. The weed cannot sustain this kind of rapid growth. The weeds will wither, fall over, and eventually die.

Dying Weed


2,4-D comes in several different forms, including liquids, granules, and dust. It is easy to find weed control products that contain 2,4-D. In the U.S., there are over 1,000 products that have this compound!

2,4-D is most often available as an amine salt. 2,4-Dichlorophenoxyacetic acid is just that – an acid. An amine is a compound with a single nitrogen atom. 2,4-D amine weed killer is a more stable form than the acid on its own. It will also break down more quickly and have less of an environmental impact.

What are the benefits of using 2,4-D?

2,4-D is an inexpensive and effective way to control weeds without harming your lawn. It is easy to find and easy to apply.

When is the best time to apply 2, 4-D?

When to spray 2,4-D on the lawn? Weed control is best applied in the spring when the weeds are young. You may also want to apply a final round of herbicide in the fall, as well – but keep in mind when you overseed.

What conditions should I apply 2,4-D weed killer?

In order to get the best results from 2,4-D herbicide, apply it 2-3 days after mowing. Look for a day with temperatures under 90 degrees. If the weather is too hot, the 2,4-D may actually harm your grass.

Don’t spray on windy days. You don’t want all your weed killer to blow away before it hits the weeds!

Check moisture levels. You want your yard to be well-watered but not too wet before you apply 2,4-D. In fact, applying the herbicide to wet grass shortly after watering may be helpful.

Wait to water until at least six hours after you apply 2,4-D, though! Remember that the compound works by soaking into the leaves of the weed. You don’t want to rinse it off right after it has been applied.

Wait at least another two days after application before mowing again.

What is the best application method for 2, 4-D?

What Is The Best Application Method For 2, 4-D

Many times, 2,4-D comes in a liquid concentrate form.  Mix three tablespoons (2.5 ounces) of the concentrate with 3-4 gallons of water. This mixture should cover 500-1,000 square feet of lawn space.

A portable pump sprayer is the easiest way to apply a liquid herbicide. Sweep the spray evenly over the grass, but do not spray so much that it leaves puddles!

How long does 2,4-D need to be on before rain?

For an amine formula of 2,4-D, apply it at least 6 hours before any expected rainfall. On the other hand, acid or ester formulas of 2,4-D only need to be applied one hour before it rains.

Will 2, 4-D kill my grass?

Since 2,4-D is a selective weed killer, it only affects broadleaf weeds. Therefore, if it is applied as suggested, it will not harm grass!

There has been some evidence that 2,4-D may harm St. Augustine grass. Therefore, if you have St. Augustine grass, give 2,4-D a pass, and look for a method of weed control that is designed for your lawn, such as atrazine.

Will 2, 4-D kill clover and crabgrass?

2,4-D is an effective herbicide against sweet clover and white clover. It is also effective in the battle against crabgrass! You should see a difference in the amount of clover, crabgrass, and weeds in as little as two months.

Does 2,4-D work in cold weather?

Herbicides, like 2,4-D, work best if the daytime temperature reaches at least 60 degrees. If cold temperatures follow the application of 2,4-D, it will take longer for weeds to die.

How do you get the best coverage with 2, 4-D?

As with any herbicide or fertilizer treatment, you should have great results if you follow the proper instructions!

Safety precautions

Before you even get started, take some important safety precautions. Wear gloves, eye protection, a mask, closed shoes, and long pants and sleeves. You may even want to wear clothing that is chemical resistant. The herbicide will be airborne as you spray it, so you want to minimize the number of chemicals that reach your skin and lungs.

Mix it up

A pump sprayer or backpack sprayer is the easiest way to get even coverage with your liquid weed control. Since 2,4-D is a concentrate, mix it according to the instructions on the label. Typically, the mixing ratio is about one ounce of concentrate per gallon of clean tap water. Then, mix the liquid thoroughly in the sprayer compartment.


Make sure the nozzle is adjusted to create a fine spray of liquid. Then, use a sweeping motion to distribute the herbicide over the grass evenly. The grass should look wet, but there should not be puddles.

Avoid touching the lawn with your bare skin immediately after application. Keep children and pets off of the yard until the grass has completely dried.

Avoid spraying shrubs, bushes, vegetables, and flowers. This is because 2, 4-D could harm your plants.

2,4-D Application

Clean it up

After spraying your lawn, thoroughly rinse the tank of your sprayer. If you use the sprayer for your plants, any residual herbicide could harm the plants. Wash your clothes and shower once you are done.

Is 2,4-D safe?

How does 2,4-D affect people?

Fortunately, 2,4-D is relatively low in toxicity. So if you get it on your skin or breathe in a small amount, your body will not readily absorb it. However, it can still cause eye irritation, skin irritation, coughing, and burning in the lungs.

If you get 2,4-D on your skin, wash it off immediately. Some users have reported severe eye inflammation. Always wear eye protection during application. If the weed killer gets into your eyes, immediately flush them with cool water.

However, if 2,4-D is ingested, it can be very toxic. If anyone drinks 2,4-D, call poison control immediately and get them medical attention. It can cause headaches, vomiting, diarrhea, confusion, kidney failure, and muscle damage.

How does 2,4-D affect the environment?

2,4-D amine salts have the least effect on the environment. This is because the salts break down quickly. In about 1-14 days, half the amount in the soil is completely broken down. In other words, the half-life of 2,4-D amine salts is 1-14 days. The bacteria in the soil help break down the herbicide, but water alone can also break down 2,4-D amine salts.

Pure 2,4-D in its acid form takes much longer to break down. The half-life of the acid is around 186 days.

How does 2,4-D affect wildlife?

Again, the amine salt version of 2,4-D is much less toxic. It has been found to be mildly toxic to fish and other aquatic animals. The toxicity is mild to moderate for birds only if they eat it and will not affect nests or eggs. It is considered to be non-toxic to bees and other beneficial insects.

The acidic form of 2,4-D can be more dangerous for wildlife. For example, if it gets into waterways, it can kill fish.

On Sale
Southern Ag Amine 2,4-D WEED KILLER, 32oz - Quart
  • Low, economical use rate of 1 to 4 pints per acre
  • Controls many broadleaf weeds & woody plants
  • Use in turf, pastures, rangeland, ditch banks, fences…

Final Thoughts

2,4-D is a safe, effective, and inexpensive way to obliterate your weed problem if it is used correctly! As a selective herbicide, it targets those pesky weeds without harming your grass. Follow all instructions and safety procedures for a weed-free, healthy lawn!

Last update on 2024-07-15 / Affiliate links / Somes Images and Data from Amazon Product Advertising API