Best Time to Apply 2-4-D for Weed Killing [Guide]

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Are you thinking of applying the 2-4-D but you don’t really know where to start and how to go about using it? This exercise can be stressful, especially if you don’t know what should be done, how, and when.

If you have a piece of the land that has proved out of control with weeds, hand pulling can help but can you do that for the whole land? It isn’t easy and would take you a lot of time.

That’s where 2-4-D comes in; usually, the best in eliminating weeds that otherwise would be impossible to deal with without the herbicide. 

You are required to know several things about 2-4-D. and in this article; we will be discussing in detail everything you need to know about the application of the 2-4-D herbicide. Let us start with the factors one should consider before applying herbicides.

Factors To Consider For Successful Application Of 2-4-D

2-4-d Application

One should consider several factors right before applying the 2-4-D because taking the proper procedure is the begging of a successful journey to eliminating weeds.

While different herbicides come in different directions, there are common factors that should be observed to ensure effective and successful application and the following are the factors to consider.

Moisture Level

When applying the 2-4-D, one ought to be careful of the moisture level in the field. If you happen to use 2-4-D when there are high levels of moisture in the area, the likelihood of the 2-4-D to fail is very high.

Why is this possible? High levels of water in the field will lower the effective concentration of the herbicide. Besides, the application of the 2-4-D with high levels of moisture will lead to run off, distributing it to undesired areas.

Temperature Levels

Like it is with different agriculture sectors, the application of herbicide depends on temperature, and 2-4-D is not an exception.

It works well with warm temperatures, relative humidity, and the favorite conditions of applying it. However, take care of the humidity levels as they may end up causing the same challenges as outlined in factor number one.

Additionally, a temperature inversion can also lead to off-target drift when applying the herbicides. When the warm air rises and is replaced by cold air may cause the herbicides to remain airborne till the end of the inversion.

By that time, the applied herbicides may have gone drastically off-target, which means herbicide application that has missed the intended purpose negatively impacts other areas.

Speed Of The Weed

The speed of the weed is another factor that one should consider for the effective application of the herbicide. Although it can be such a tedious job to wait for the optimal wind speed, your patient is worth every minute when you remember the adverse effects if you apply herbicide with inappropriate wind speed.

According to the University of Minnesota, the ideal speed should range between 3 to 7 meters per second. Anything beyond 7 meters per second can interfere with the application and cause the drift off target. 

On the other hand, any speed below 3 meters per second would result in the ineffective application if temperature inversions occur by any means. Consequently, be mindful of the direction of the wind as it can be beneficial and devastating at the same time.

Choose The Correct Nozzle

Effective herbicide application also relies a lot on the kind of nozzle used. The size of droplets solely depends on the nozzle and spray pressure which determines the amount of spray, uniformity of the application, and the overall coverage.

With the right nozzle, you can regulate the droplet size while allowing the applicator to have the right coverage with the herbicide.

The requirement for the nozzle and nozzle related specification should be labeled on the herbicide. Ensure the nozzle, and the sprayer is clean and working, and calibrated in the right order before you have your way to the field. This guarantees you a smooth time in the area as the worn-out and unclean lawn equipment can result in uneven applications.

Best Time To Apply 2-4-D

Application of the 2-4- D can be a challenge if you don’t know the right time to use the herbicide. It appears that temperature should be at least 70 degrees or even above for optimal results.

Research has shown that when 2-4- D is applied when temperatures are above 90 degrees, it causes harm to the plants. The best time to spray is in the afternoon when temperatures are between 80 and 85 degrees, and it is not expected to rain during the rest of the day.

Consider the soil’s moisture and ensure that it is high and the plants are growing as this would give you maximum results. It is always recommendable to spray immediately after it has rained provided you have the right temperature. However, be mindful of when it is likely to rain again as you require 6 to 10 hours of no rain from spraying.

The scientist from the Dow Agro sciences forages claims that since pastures contain general weeds, it would be recommendable to apply the 2-4-D when growth is actively taking place. People are discouraged from applying herbicides during spring because it is less effective compared to fall applications.

The time when development is actively taking place is early in the season. During the fall between September and November is the appropriate time to fight broadleaf weeds by applying the herbicide.

During fall, the weeds are transporting food from their foliage to their roots to get prepared for the winter. When you use herbicide during fall, it falls on the leaf and gets absorbed by the leaf weeds foliage and transported directly to the roots together with carbohydrates, leading to the destruction of the weeds.

2-4-D Application Instructions

Weeds don’t just detract from the garden’s visual appeal but also take away from the desired plants or crops. However, with 2-4-D herbicides, you have full control over all weeds in your garden.

You can use the 2-4-D herbicide before you plant your garden because if used after planting, it can damage flowers, fruits, and vegetables found on the ground.

Now, how do you go about applying the 2-4-D herbicides? Put on the relevant protective gears before you do any mixing or spraying. You can wear safety glasses, socks, foot wares that are chemical resistant, along with sleeved shirts, don a chemical-resistant apron, and pants. 

On the herbicide’s spray tank, attach your flat nozzle tip and get ready to spray when the wind moves at a speed range of between 3 to 7 meters per second. Have the pressure set to 20 pounds per square inch, start the tank’s agitator, and ensure it runs throughout the mixing and application process.

Get a half-gallon of clean tap water and add between two to three tablespoons of the 2-4-D herbicide. Get another half-gallon of clean tap water to make a full tank. Add one tablespoon of a surfactant such as the liquid dish soap to the mixture. The purpose of the surfactant is to help the 2-4-D not to stick to the weeds.

You can now apply the 2-4-D herbicide on the individual weeds and the top leaves and bottom of the leaves, stems, and flowers. Ensure you don’t breathe in those fumes from the spray and make sure you don’t come into contact with the herbicide with your bearskin.

How Does 2-4-D Work?

how to apply 2-4-d

The way the 2-4-D herbicide works is quite fascinating. The 2-4-D herbicide gives the broadleaf a form of symbolic “cancer” causing it to grow uncontrollably up to its death. This occurs as a result of the destruction of vital tissues.  This chemical is a selective weed killer following the criteria it applies.

The 2-4-D herbicide affects only the broadleaf weeds and not the grasses because of broadleaf and grass transport chemicals through different mechanisms through their leaves. Broadleaf has a growing point at the tips of their leaves while grasses grow from their base. Thus, the 2-4-D herbicide can kill the broadleaf weed while sparing the grass.

One reason why the 2-4-D is so popular is its low price and its magic in eliminating weeds. Over 1,000 herbicide products contain the 2-4-D, and it’s often mixed with other active ingredients like Dicamba. The 2-4-D herbicide application can kill weeds like dandelion, clover, crabgrass, and others in as quickly as two months.

Precaution And Safety Tips With 2-4-D

Until the time we know more about the 2-4- D, the following are precaution and safety tips we are expected to adhere to

  • If you find it hard to dissolve 2-4- D in hard water, alternatively, you can dissolve it in soft water (cistern). For the people who are living in the city, there is no trouble with water. You can dissolve in lukewarm water and mix it with the right amount of water for spray, and you are less likely to experience a challenge.
  • If you are spraying on an area where you don’t want to hurt the grass, you are recommended to spray only when temperatures are below 90 and most preferably between 80 and 85 degrees. However, if you realize that the grass is hurt, you can water it thoroughly with the sprinkler.
  • Do everything to avoid the spray’s drift if there are valuable shrubs around that may get injured when drifting occurs. You can spray during or when the wind speed is relatively low. Ensure you keep the nozzle close to the ground and pointed away from the plant you want to protect. A soft pressure knapsack spray is perfect for spraying.
  • Spray the weed to the extent of light dew but ensure it is not too much to run off and hurt the grass. Also, ensure that you use the 2-4- D in the right amount and directions as indicated on the package.
  • If you use the same spray for 2-4- D to spray insect and disease control in your garden, make sure you thoroughly wash it using kerosene and a baking soda solution. Rinse the spray with clear water after you have washed out the spray. Plants have been hurt for using a spray that has not been cleaned well.
  • Keep off spraying the areas again until the herbicides have dried up completely and no animal should feed on the sprayed areas. The remaining herbicide should be disposed of at your local waste disposal center. Wash your tank and any other reusable operator before storage and the protective clothing in a separate laundry load.

Best 2-4-D Alternatives 

Lesco Weed Killer

lesco herbicide

Lesco weed killer is an alternative to 2-4-D and a complete industrial herbicide, turf, and ornamental weed control. Lesco is more effective when applied during the early spring to prevent crabgrass and other annual grassy-type weeds from growing.

Lesco weed killer is a postemergence and systemic without any residual soil activity. It gives you a wide range of control of different weeds, including annual, perennial weeds, woody brush, and even trees. Lesco is made as a water-soluble herbicide and contains a surfactant.

It combines the 2-4-D, triclopyr, and fluroxypyr, making it provide a quick and long-lasting crackdown of the tough weeds. With Lesco, you can control weeds, including the Clover, dandelion, groupivy, oxalis, purslane, spurge, and thistle.

You can always find the weed killer either as a fertilizer combination product or as a liquid Herbicide. It will not stain driveways, sidewalks, and other non-target areas and can cover approximately 10,000 sq. ft. Ensure you apply this Herbicide with a rotary spreader.

Horsepower Weed Killer

horsepower herbicide

Horsepower weed killer is a highly concentrated herbicide and comes with a broad spectrum control of broadleaf weeds. Horsepower herbicide is a three-way selective emergent herbicide, meaning it contains triclopyr as one of the active ingredients that are deemed useful in killing hard to kill weeds.

Weeds that horsepower herbicide kills include chickweeds, dandelions, Clover, knotweed, oxalis, plantains, among others. It is recommended to treat spots on the athletic field, golf course, cemeteries, lawns, parks, and most importantly, on 2-4-D sensitive areas. Horsepower herbicide can treat up to four acres of land per gallon.

Cool Power Weed Killer

cool power selective herbicide

Cool power herbicide is a post-emergent selective herbicide used to control dandelions, plantains, oxalis, spurge, and other broadleaf weeds in chilly weather conditions.

This Herbicide is perfect for controlling weeds during winter, dormant warm turf seasons, and application during the early season in transition zones and cool-season climates. 

Avoid spraying to the newly seeded grasses until well established. It is advisable not to apply more than four pints of cool power herbicide per acre in a year. Do not apply more than two times per year with a minimum retreatment interval of twenty-one days. Ensure you reseed no sooner than 3 to 4 weeks immediately after spraying the cool power product.


Question: What happens to the 2-4-D   after getting into the soil?

Answer: When 2-4-D gets into the soil, it undergoes different stages in the environment depending on its form. It breaks down while in the ground, and half of the original amount is eliminated within 1 to 14 days. One of the forms of the 2-4-D, the butoxy ethyl ester is said to have more half-life in aquatic sediments of 186 days. Half-life is the breakdown time of the 2-4-D.

Question: How might I be exposed to 2-4-D?

Answer: You may get exposed to the 2-4-D   if you are applying and get on your skin, breath it, or eat or when you smoke without washing your hands. You may also get exposed if you touch plants that are still wet with spray. However, you can minimize exposure by following instructions on the label carefully if you are using products with 2-4-D. You can also avoid grass and plants that have been sprayed until they are completely dry.

Question: How dangerous is the 2-4-D?

Answer: The 2-4-D is generally moderately toxic to birds and mammals, slightly toxic to fish aquatic invertebrates. It is typically non-toxic to honeybees.  The ester form of the 2-4-D    is greatly harmful to marine animals and should be used carefully as directed on the label to ensure no harm is caused to the animals.

Conclusion: When to Apply 2-4-D

It is advisable to implement 2-4-D when development is taking place aggressively. People are not encouraged to use herbicides during the spring because they are less effective relative to fall applications. The moment when growth is taking place aggressively is early in the season.

Between September and November, it is necessary to control large-leaf weeds (broadleaf weed control) by administering the herbicide during the fall (e.g. also referred to as winter annual weeds).

In the winter, weeds move food from their leaves to their roots to prepare for the winter. If you use herbicide during the fall, it falls on the leaf and is absorbed by the leaf weeds leaves and transferred straight to the roots along with carbohydrates, contributing to the death of the weeds.

Further Reading on Lawn Weeds & Weed Species:

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