Skip to Content

When to Spray 2,4-D on Lawn – 3 Things to Know Beforehand!

Sharing is caring!

It feels great to see your hard work being paid off in the form of healthy plants.

Most of us gardeners patiently wait for the day our plants start growing exponentially. However, one thing can destroy the beauty of our garden and take away all of the plant resources, thereby killing them.

Weeds are unwanted plant growths that take up space in your garden. Nobody likes weed plants—they are unsightly and hard to get rid of.

If you have stubborn weed growing in your lawn, you can take care of it by spraying it with herbicide. One of the best herbicides in the market for treating lawn weeds is the 2,4-D spray.

The 2,4-D spray is used to fight off broadleaf weed. But to be effective, you must pick the right time to spray the herbicide in your garden.

So, you might be wondering when to spray 2,4-D on lawn.

This is a bit tricky to understand. If you are stuck in this dilemma with no information, keep reading as we explore the answers to your question.

Man spraying herbicide—when to spray 24 d on lawn
When to spray 2,4-D on lawn? – Image via Prakash Aryal.

What Is 2,4-D Herbicide?

The full form of this herbicide is 2,4-Dichlorophenoxyacetic acid, which is used to kill broadleaf weeds in the garden.

The great thing about this herbicide is that it is selective in its function, which means that spraying it on the lawn will only kill the broadleaf weed and not your plants.

The function of the 2,4-D Herbicide depends on the plant growth hormone auxin present in the spray.

The weed absorbs the growth hormone, which is immediately catapulted into rapid and excessive growth.

While this may seem counterintuitive, the rapid growth is not sustainable for the plant, and it will soon die after being unable to keep up.

What Weeds Can 2,4-D Spray Kill?

The 2,4-D spray is an effective chemical; however, you cannot use it without any barrier or in any place to kill the weed.

  • This herbicide kills only broadleaf weeds, so if you are dealing with some other kind of weed plant, it might not work.
  • The product is mainly organic.
  • Moreover, the 2,4-D spray is manufactured with ingredients that are not suitable for use in vegetable or crop gardens.
  • You can use it on lawns with ornamental plants, driveways, patios, and other such places.
  • You should also not worry about the herbicide killing your grass, as the only grass that a 2,4-D spray can harm is nutgrass. For all other grass types, you can use it without worry.

Make sure the weed plant has a solid base in the soil before you spray to keep the other plants and grass safe from the chemicals in this herbicide.

When to Spray 2,4-D on Lawn?

When to spray 2,4-D on lawn, you ask? There are certain conditions you need to keep in mind before spraying 2,4-D in your garden, or it might not work.

The best time to spray this herbicide is when the weed plants are still young and have just started to grow.

This is usually during the springtime, but some weed varieties have the growing season in the fall or summer. So you can adjust the spraying time accordingly.

Make sure you don’t use herbicide on your lawn just after you’ve planted your grass or other seedlings. Give a time of at least 5–6 weeks before spraying the garden with 2,4-D spray.

There are more environmental requirements you should be careful of to ensure the proper functioning of this herbicide.

A Suitable Temperature

The ideal temperature for spraying 2,4-D herbicide ranges between 60 to 85 degrees.

This is the temperature range at which the weeds usually start growing, so you should target this temperature for the spraying schedule.

You must choose a temperature where the possibility of absorption of the herbicide is maximum, ensuring the weed plants’ complete extermination.

However, the temperature should not be higher than 85 degrees as high temperatures can lead to rapid evaporation of the chemical, leaving the weed behind with no significant effect.

The 2,4-D herbicide can also work in cold weather, and it is not entirely ineffective in lower temperatures, but it may take a bit longer for the effects to show.

So, the sweet spot for spraying the herbicide is the temperature when the weed plants have started growing, but it is still not too hot outside.

That would be anywhere between mid to late spring, as the environment is just at the right temperature.

Related article: 5 Best Weed and Grass Killer for Fence Lines (Detailed Reviews)

Rain and Moisture

The moisture level for spraying the 2,4-D herbicide is a bit tricky.

  • You should never spray the herbicide when the soil is overwatered or too soggy.
  • If there is too much moisture in the soil, the herbicide will get diluted and may not have a substantial effect on the weeds.
  • Also, high moisture levels can cause the herbicide to run off with the water leaving nothing behind.
  • But spraying the herbicide on dry, cracking soil is also not recommended as the chemical might not be adequately absorbed.
  • A little moisture is necessary for the complete absorption of the herbicide.
  • So, ensure the soil is damp but not flowing with water or cracking dry.

Considering how you need to get the moisture level right in the lawn, you also must be careful about the rain conditions in your area.

Rain can cause the herbicide to run off, especially when it occurs right after you have sprayed, not giving the chemicals enough time for absorption.

So, you should always check the forecast for rain and choose a day when you can safely spray the lawn without high rain chances for the next few days.

The herbicide needs at least one whole day to be absorbed and dry off, so keep that in mind. If it had rained before your spraying schedule, let the lawn completely dry before you proceed.

Another point to remember is to choose the time of the day wisely.

Make sure to spray the herbicide between early morning and midday. That is because you should allow the morning dew to dry before applying the herbicide.

Here’s a video guide on spraying 2,4-D on your lawn:

Kill Weeds but Not Grass with “2,4-D” – YouTube

Spraying 2,4-D After Mowing

If you spray 2,4-D herbicide right after mowing the lawn, there are reduced chances of it working properly.

The herbicide works by covering the weed plants and getting absorbed into them, so it is better if some growth has erupted from the soil.

Mowing the lawn may cut off the weed plants as well. Without the weeds, the chances of the herbicide working are less.

So, you must ensure that the weed has some growth before you apply the herbicide to the soil.

Choosing a time right after mowing the lawn is not a good idea. Moreover, it would be best to remember not to mow the lawn soon after spraying the herbicide.

If you have just sprayed 2,4-D on the lawn, wait 3–4 days before carrying out your next mowing session.

Tips to know Before Applying 2,4-D

You must follow some essential tips before applying the herbicide to your lawn.

Safety precaution is essential before your begin spraying.

A sprayed chemical can quickly come in contact with your skin and be inhaled. So, you must take steps to protect your skin and lungs.

  • Get some protection goggles, gloves, and a hat as well.
  • Wear clothes that are resistant to chemical absorption.
  • Also, wear a mask covering your nostrils and mouth.
  • You can spray the lawn only after you have covered yourself properly.
  • Make sure to wash all clothing and keep it separately after use.
  • Use a spray container with a nozzle with a fine streak of spray to be more even and targeted.
  • Keep the children and pets away from the lawn for a few days after spraying the garden, and make sure you don’t touch it either with your bare hands.
  • If you use the same spray container for the other plants, wash it off properly before using it for normal watering.
  • Wash your hands properly and take a bath.

The good thing about 2,4-D herbicide is that it is not extremely harmful in small amounts.

Compare N Save 2 4 D Amine Broadleaf Weed Killer—when to spray 24 d on lawn
Compare N Save 2 4 D Amine Broadleaf Weed Killer — via

So, if a little chemical gets on your hands or even if a small amount is inhaled, it will not be detrimental to the person, but you should still keep the above points in check.

The immediate step would be to rinse the area where the chemical touched with plenty of water. Use cool water to ease the pain or rash.

However, seek immediate medical help if you think it’s something serious.


I hope now you know when to spray 2,4-D on lawn.

Spraying herbicides can be tricky as you have to consider several points.

You can apply 2,4-D herbicide on your lawn safely without worrying about killing off other plants, but you must ensure some conditions before doing that.

After fulfilling other requirements, ensure you are spraying at the right temperature, time of the day, and moisture level.

Don’t overdo the herbicide.

Always keep it in moderation, and remember not to use it in your crop garden. Take notes, and you will be ready to eliminate the stubborn weed in your lawn.