How Long Does 2,4-D Take To Work? [TIMELINE]

We have all heard about the incredibly powerful and effective selective herbicide 2,4-D. It takes care of most unwanted broadleaf weeds, and better yet, weeds don’t ever grow in the areas that have been treated with 2.4 D. But now that we know how well it works, how long does 2,4-D take to work after you have applied it to your weeds?

Forty-eight hours after the application of 2,4-D, plants will start showing signs of wilting and dying. However, 2,4-D is a slow-acting herbicide and needs 14 – 30 days for full results. It’s a highly effective weed killer that is safe to use on your lawn and isn’t harmful to animals or children.

If you are about to apply 2,4-D to your lawn but are unsure when to expect results, then you have come to the right place. This article will discuss how long it takes for 2,4-D to work, how it works, and all the special features that make 2,4-D a herbicide to be reconned with.

How long does 2,4-D take?

Due to its powerful weed-killing properties, 2,4-D should only be applied once a month or less. Applying 2,4-D more than recommended will cause the soil to have a level of herbicide that is too high and can damage or even kill your grass.

For active and visible results to start showing, it will take approximately 2 – 4 weeks. This time frame depends on the proportion or ratio of 2,4-D to water. If your ratios are correct, you will see results within a fortnight or month after application. 

You will see a marked difference in the areas that you applied 2,4-D, as weeds will start dying out, and they will never grow in that area again. There is no need to apply it more than once a month because it kills all the weeds to which you have applied it.

It isn’t hard to understand why 2,4-D is one of the most popular selective herbicides on the market. Customers prefer this herbicide due to its powerful effects and product features, including:

• Effectively kills weeds without damaging the grass
• Can kill a large variety of broadleaf weeds
• In not linked to any health concerns
• It kills weeds at a very high rate
• It is not harmful to animals or people
• you can use it on most turfgrass species

If you want to increase the effectiveness of 2,4-D, try the following recommendations:

• Apply when there is a 6–8-hour rain-free forecast ahead.
• Choose a low to no wind day to apply 2,4-D to prevent increased evaporation and overspray.
• If it has rained, wait at least 6-8 hours before applying 2,4-D.
• The ideal temperature for applying 2,4-D is 65 – 85 Degrees Fahrenheit – If temperatures are too high during the application, it could harm your grass. If temperatures are too low, the 2,4-D will be ineffective.

Is 2,4-D Safe To Use Around Food Or Herb Gardens? 

Although 2,4-D is not harmful to your grass, animals, or children, you should never use it near growing food or herbs. If you have used it around growing food, you will have to wait a whole year before planting any edibles in that area again.

How Does 2,4-D Work? 

2,4-D changes how the cells of the weed plant grow, and the level of toxicity depends on which chemical form it is. 2,4-D is a broadleaf weed killer and causes the cells inside the tissue (responsible for carrying nutrients and water) to divide and continue growing uncontrollably. 

The plants struggle to keep up with the rapidly growing rate as the cells multiply too quickly. Ultimately the plant dies. This is called an auxin-type herbicide. 2,4-D has the power to kill the following unwanted weeds;

• Toadflax 
• Ragweed 
• Sagebrush 
• Coffee weed 
• Pennycress 
• Sweet clover 
• Jewelweed 
• Pepper weed 
• Velvetleaf 
• Canada thistle 
• Red clover 
• Nettle 
• Alder 
• Goldenrod 
• Virginia creeper 
• Wild carrot 
• Wild parsnip 
• Tumbleweed 
• Purslane

Unfortunately, 2.4 D does not kill crabgrass. Where we consider crabgrass as a weed, 2.4 D identifies it as grass and leaves it alone. 

Nutgrass is the only species of grass that 2,4-D can kill, and it can also damage turfgrass such as Saint Augustine grass if the 2.4 d is not hi-yield 2,4-D. It can also cause damage to the blades of dormant Bermuda grass in early spring or late winter.

Is 2,4-D Toxic To Birds Or Other Wildlife? 

Fortunately, birds are unaffected by 2.4 D. If you spray it on an egg, it will still hatch, and the chick will be normal and unharmed. Unfortunately, fish are affected by 2.4 D. Most ester forms of 2.4 D are highly toxic to fish. 

Aquatic animals are affected by the salt forms of 2.4 D, especially when the temperature of the water rises. 2.4 D is nontoxic to honeybees and non-hazardous to beneficial insects. 

Mixing Ratios, Coverage, And Application Of 2,4-D

Always read the instructions of any chemical product before you use it. Many products contain 2,4-D, so each ratio and application method will differ from one product to another. 

If you deploy 3 – 4 Oz (85 to 113 ml) of your hi-yield 2,4-D selective weed killer across 1 – 3 gallons (4.5 – 14lt) of water, you have enough to cover an area of about 1,000 sq ft. Remember that the ratios of 2,4-D with water will differ if you prepare a mixture for a smaller surface like a lawn. 

Generally, the mixing ratio is 2.5 Oz (+/- 5 tbsp) of 2,4-D (not Hi-Yield) to one gallon of water. This amount of 2,4-D mix will cover approximately 400 square feet of lawn.

Top 5 2,4-D Weed Killers

1) Q4 Plus Turf Herbicide – kills cool-season turfgrasses such as ryegrass, bluegrasses, Bermuda grass, tall fescue, and more.

2) Tordon RTU Speciality Herbicide – ready to use, no mixing required.

3) Hi-Yield 2,4-D Selective Weed Killer – selective, post-emergent, liquid concentrated herbicide. Kills various poisonous plants and broadleaf weeds.

4) Trimec 992 Broadleaf Herbicide – used by professionals. Contains higher 2,4-D levels for faster results.

5) Helena Crossbow Herbicide – targets woody plants and brush (poison oak, blackberries) and perennial and annual broadleaves.

Interesting Facts

In North America, 2,4-D, a compound chemically known as 2,4-Dichlorophenoxyacetic acid, is the 3^rd most commonly used herbicide. 

According to a study conducted by the US Department of Agriculture in 1996, an estimated increase of $16 million in costs for fiber and food to consumers would result if 2,4-D were to be taken off the market.

Wrapping Up

So, even though 2,4-D takes 2 – 4 weeks to show full results, it is definitely worth the wait, as you will be rid of weeds once and for all.

It is an especially great product because it causes little to no harm to animals and the environment, everything you want in a herbicide!