As beneficial as dandelions may be to humans, they can be among the most harmful perennial weeds for lawns. Arming yourself with one of the best dandelion killers is vital if you want to ensure a clean and healthy lawn all year round.
Top 3 - Dandelion Killers
8 of the Best Dandelion Killers
My top picks should help you bypass research and start treating the problem before it gets out of hand.
This weed killer comes in 32oz and one-gallon canisters. The formula contains Dimethylamine salt in the proportion of 46.3%. As such, it’s an ideal broadleaf weed control substance to maintain your lawn, ornamental turf, or backyard miniature golf course in perfect condition.
The formula is effective against some woody plants too. It’s also quite potent, given the concentration of the active ingredient. The recommended mix is up to three tablespoons of 2,4-D Amine Weed Killer to between three and five gallons of water.
That’s enough to treat up to 1,000sq.ft. of lawn or non-crop sites. I should also point out that this one doubles as a pre-emergent and post-emergent herbicide. Make sure you spray it with low water pressure and in a broad dispersal pattern if you can. Not just for uniformity but also to avoid dousing your lawn or turf in it.
The Ortho Weed B Gon weed killer comes in a ready-to-use canister. It holds one gallon of Ortho’s top weed killing formula, and you also get a wand applicator, which is ideal for spot treatments. This product kills over 250 common weeds, including dandelions.
Due to the unique formulation, you should be able to see results in just a few hours. At least after doing spot treatments. What I like about it the most is that it also targets the root system. That should help prevent dandelions from reemerging, at least in the same spot.
You’ll surely recognize the main active ingredient, Dimethylane salt of 2,4 D Acid, although in a much lower concentration than in some other formulas. Dicamba acid and Dimethylane salt of Mecoprop-p Acid are also in the mix. So this weed killer is a lot more potent than it looks.
A single 32oz canister of concentrate should give you enough formula to cover up to 5,000sq.ft. You might also like to know that this is a useful crabgrass control substance and that it can also handle poison ivy.
If you’re looking for an organic alternative to most herbicides, then Green Gobbler’s 20% vinegar weed killer may be the right solution for you. Its effects start showing in a matter of hours, with full desiccation achieved in under one day.
This formula can kill dandelions, moss, white clover, crabgrass, and many other weeds. I recommend it for residential, commercial, and even agricultural use, as long as you follow the instructions to the letter.
This vinegar weed killer is not suitable for broadcasting applications. It’s better when used as a spot treatment weed killer. Of course, it’s not ideal for lawn treatments, but you can still use it to tend to your driveway, flower beds, etc.
Available in 16, 32, and 64oz bottles, the Roundup Concentrate Plus is a very impressive weed killer. It’s best used with tank sprayers and against some of the more resilient weeds and grasses. It will make short work of dandelions.
You can use it around fences, foundations, shrubs, flower beds, and even in lawn replacement applications. The formula also becomes rainproof in around half an hour, which I think is fast enough for year-round use.
You should see results in less than half a day. However, complete desiccation may take more than a week, sometimes even two. It’s not the fastest dandelion killer, but it is relatively safe to use, compared to other alternatives.
Note that the formula is not ready to use straight out of the box. You’ll have to mix it with water at a ratio of 6oz concentrate to one gallon of water. It should be enough for up to 300sq.ft.
If you’re looking to get rid of weeds and dandelions before they even have a chance to grow, this could be the weed killer for you. The Preen Extended Control formula contains Trifluralin and Isoxaben, which make up almost 2% of it.
Thanks to these two active ingredients, this isn’t the safest control substance to use directly on lawns, around edible plants, or even in water gardens. However, I do recommend it in combination with mulch.
Mix this formula into the mulch you use on landscape beds or perennial flower beds. After water activates the substance, it should soon create a weed barrier. It goes as far as 3” below the soil, thus preventing dandelions and other weeds from growing.
It’s best not to use the Preen Extended Control Weed Preventer more than two times a year. Ideally, you should use it once during the growing season and once more after about six months.
The PBI Gordon 2,4-D Amine Weed Killer is one of the most effective and popular dandelion killers. This concentrate is an economical control substance for many broadleaf weeds.
It’s an ideal choice if you want to treat lawns, pastures, or even agricultural plant beds. A single gallon should be enough to treat up to four acres of land.
If there’s one significant drawback, it’s how much time this weed killer takes to become rainproof. Compared to other similar products that may take around one hour, this formula will take up to eight hours to dry and become rainproof.
That said, you can use it with various sprayers too, such as hose-end, pump-up, or even tow-behind models. That compensates for the slower reaction, as it makes the formula versatile and usable in various applications.
This concentrate is available in 16, 32, 40, and 64oz bottles. Therefore you can use it no matter how big or small your property is. It’s also one of the fastest-acting dandelion killers, given that visible results show in as little as three hours.
What I like about this formula the most is that it becomes rainproof in 15 minutes. That makes it ideal for last-minute weed treatments. It’s best to use it with a tank sprayer, but you can also use it for spot treatments.
Unfortunately, none of the bottles come with sprayer attachments or tools. To get the most out of the Spectracide Concentrate, you should make sure that you cover the leaves of targeted weeds completely. Unlike other herbicides, this one won’t get to the root system. Therefore, dousing the foliage is the best course of action.
Where and How to Use Dandelion Killers
You can categorize weed killers in many ways. But here are two types that I find most important – those that are safe for lawns and those that aren’t.
As you’ve noticed by now, from reading the reviews, not all herbicides have the same intended uses or the same dangers associated with them. Some dandelion killers may be entirely safe to use on lawns and turfs.
However, others should be used only in spot treatments. Usually, if the label indicates a weed and grass killer formula, you will want to avoid using that on your lawn. Unless, of course, you plan on replacing a patch after the treatment anyway.
In professional terms, these are called selective and non-selective dandelion killers or herbicides.
Can You Prevent Dandelion Emergence?

Yes. Some herbicides also qualify as pre-emergent weed killers. It means that you can mix them with mulch and feed them into the soil before plants start to grow. Most pre-emergence weed killers are selective herbicides that shouldn’t affect other plants.
Instead, they’ll create a weed barrier in the soil, just a few inches under the surface, which will prevent dandelions and other weeds from sprouting.
You can also allow your lawn to grow taller—the taller the grass, the less light available for dandelions and other weeds to grow. Of course, keeping your lawn healthy is the best way to ensure you won’t need systematic dandelion removal treatments.
Chemical vs. Organic Dandelion Killers
Neither option is without some risk. Some natural solutions are so potent, especially those made from acetic acid, not table vinegar. A high concentration of vinegar could also affect your edible plants, grass, ornamental plants, etc.
On the other hand, chemical herbicides will be more effective, whether you’re thinking of broadcasting or spot applications. Manufacturers have a long list of active ingredients to tap into, so the formulas are always improving.
That said, it’s not precisely the environmentally-friendly approach, even if you follow the instructions to a tee. The only thing I can recommend is to make a fair assessment of the situation first. After that, pick the most appropriate product based on weather patterns, how much square footage you want to cover, where you want to treat, and so on.
The Importance of Rainfast
Rainfast is a fancy way of saying how long does it take for a solution to become rainproof. It is an essential aspect of any herbicide, whether you use it for grass, weeds, or both. If you live in an area that sees plenty of rain, your choice may heavily depend on the rainfast rating.
For example, some herbicides can take 30 minutes to one hour to dry and become immune to the rain. Others can take up to eight hours to dry. Some formulas will dry in almost no-time – the current record holder dries in 15 minutes.
The thing to remember is this. A weed killer might dry fast and be virtually weatherproof, but it doesn’t mean that it’s also the fastest dandelion killer.
How Fast Do Herbicides Work?
That varies greatly, as much as the rainfast of an herbicide. Some dandelion killers can solve your problem in under 24 hours. Other formulations may take up to two weeks to destroy dandelions down to the root system.
Choosing a rate or speed of effectiveness is situational. If you’re in the landscaping business, then you might need something that acts faster. It will allow you to replace any affected grass much quicker.
If you’re not sure what to do or you just don’t want to use anything too aggressive and toxic, you could opt for a slower dandelion killer. That way, if you make a mistake during the application, you may be able to save other plants you’ve sprayed unintentionally.
The Dandelion Population Can Get Out of Control
Not everyone is keen on eradicating dandelions off their property. But if you think about it, a weed is always going to be a weed, no matter what other benefits it may have. Dandelions can ruin your landscaping and cause serious harm to sensitive lawns by taking away precious nutrients.
As you can see, your options for dealing with this are almost endless. And, now that you know the types of herbicides at your disposal, methods of application, and what to expect, deciding on a weed killer should be a lot easier.