Oh, are thistles taking over your lawn, garden, or farm? Do you find yourself constantly yanking at them, only to see them come right back a few days later? Fear not! In this article, we will help you pick the best herbicide for thistles so you can give those prickly nuisances the knockout punch they deserve. Say goodbye to unwanted weeds and hello to a beautiful landscape with these effective solutions for thistle control.
Here are the best herbicides for thistles you can buy in 2023:
- Best For Flower Beds: Green Gobbler 20% Vinegar Weed & Grass Killer
- Best For Vegetable Gardens: Compare-N-Save 75323
- Best For Turfgrasses: Syngenta ASINPPOSPRME75447
- Best For Toughest Thistle: BIOADVANCED 704140
- Best For Immediate Results: ECO Garden PRO-Organic Vinegar Weed Killer
- Best For Actively Growing Thistles: Ortho 0204810
|6 best herbicides for thistles|
Best For Flower Beds
|Green Gobbler 20% Vinegar Weed & Grass Killer|
Best For Vegetable Gardens
Best For Turfgrasses
Best For Toughest Thistle
Best For Immediate Results
|ECO Garden PRO-Organic Vinegar Weed Killer|
Best For Actively Growing Thistles
Best For Flower Beds: Green Gobbler 20% Vinegar Weed & Grass Killer
- Best for flower beds – 20% acetic acid
- Safe and reliable - OMRI-listed and glyphosate-free
- Easy to use – including a sprayer attachment
- The sprayer could be more quality
- The vinegar is smelly
If you're here searching for an effective herbicide for controlling thistles in flower beds, the Green Gobbler 20% Vinegar Weed & Grass Killer is a great choice.
Its main ingredient is acetic acid, a high-strength vinegar that is biodegradable and approved for organic use. It packs a powerful punch and can quickly knock out thistles within hours.
Besides, the product is OMRI-listed and glyphosate-free, making it a safe and natural option for controlling weeds like thistles without the need for harsh chemicals. This means it's completely safe for flower beds.
|Green Gobbler 20% Vinegar Weed & Grass Killer Specifications|
20% acetic acid & 80% water.
20% acetic acid
OMRI-listed and glyphosate-free
including a sprayer attachment
When used properly, the Green Gobbler 20% Vinegar Weed & Grass Killer can be an extremely effective and safe way to control thistles in flower beds.
Best For Vegetable Gardens: Compare-N-Save 75323
- Safe for vegetable gardens – a low use rate of 0.75 lbs. acid equivalent per acre & post-emergence formulation
- Able to kill thistles and annual grasses - Glyphosate
- It takes some time to work
With the main ingredient of glyphosate, a powerful herbicide, the Compare-N-Save 75323 has the power to completely control thistles. This herbicide is fast acting and rainproof in one hour.
Rest assured, you can use this herbicide in your vegetable gardens as it has a low use rate of 0.75 lbs. acid equivalent per acre and is specially formulated for post-emergence applications.
Besides thistles, you can use this product for controlling annual grasses such as crabgrass, foxtail, and annual bluegrass, keeping your gardens completely weed-free and healthy.
|Compare-N-Save 75323 Specifications|
32 Fluid Ounces
a low use rate of 0.75 lbs. acid equivalent per acre & post-emergence formulation
The Compare-N-Save 75323 is effective and safe to use in vegetable gardens at the same time, making it one of our favorites.
Best For Turfgrasses: Syngenta ASINPPOSPRME75447
- Best for turfgrasses – Mesotrione 40%
- Convenient to use – including a measuring tool
- It works slowly
The Syngenta ASINPPOSPRME75447 is a systemic pre-emergence and post-emergence herbicide formulated with a proprietary active ingredient, mesotrione. So it has selective contact and residual control of thistles in turfgrasses.
Mesotrione is derived from the bottlebrush plant and has been granted 'reduced-risk' status by the Environmental Protection Agency.
We also appreciate the included measuring tool, making it a breeze to take out the product with the exact amount as desired.
|Syngenta ASINPPOSPRME75447 Specifications|
Mesotrione & Glyphosate
including a measuring tool
The Syngenta ASINPPOSPRME75447 is a good value for when you need to eliminate unwanted weeds like thistles from your turfgrasses.
Best For Toughest Thistle: BIOADVANCED 704140
- Ability to kill the toughest thistles – Vivendi
- Not easily washed off by water - a rainfast time of 1 hour
- Easy to apply – compatibility with hose-end sprayers
- No complaint
The BIOADVANCED 704140 can kill the toughest thistles due to its combination of many powerful active ingredients specifically designed to target broadleaf weeds like thistles.
Take some good examples.
Glyphosate is effective against all weeds and is used with 85% of GM crops grown globally, while Clopyralid, 24-D or Dicamba are effective against a range of other weeds such as Ragwort. For well-established thistles, the herbicide also contains Vivendi, which can be applied by either Knapsack or boom sprayer.
The total coverage area for this herbicide is up to 6,250 square feet and it has a rainfast time of 1 hour, making it easy to use and apply.
|BIOADVANCED 704140 Specifications|
40 Fluid Ounces
Quinclorac, 2,4-D dimethylamine salt, Dicamba dimethylamine salt, Vivendi, Glyphosate
a rainfast time of 1 hour
The BIOADVANCED 704140 is formulated of the most powerful active ingredients, allowing for killing the toughest thistles.
Best For Immediate Results: ECO Garden PRO-Organic Vinegar Weed Killer
- Give results within 24 hours - sodium chloride & acetic acid
- Prevent weeds from recovering - organic vinegar with a low pH level
- Safe for humans, pets, wildlife, and environment
- It has very strong vinegar odors
- Not last long
If you're looking for a quick and effective solution for thistle control, we recommend the ECO Garden PRO - Organic Vinegar Weed Killer.
Unlike many synthetic weed killers, the organic vinegar in this product does not contain any hazardous chemicals or poisons that can be harmful to humans or pets.
Its proprietary formula contains an organic vinegar base with a high acetic acid content which breaks down the cell walls of weeds and thistles, leading to rapid destruction within just 24 hours.
The organic vinegar also has a low pH level which prevents the weeds from recovering by blocking off essential nutrients and water.
|ECO Garden PRO-Organic Vinegar Weed Killer Specifications|
fermentation derived cofactor
biodegradable plant activator
sodium chloride 5%
acetic acid 8%
sodium chloride & acetic acid
The beauty of the ECO Garden PRO - Organic Vinegar Weed Killer is it brings immediate results, so you don’t have to wait for so long.
Best For Actively Growing Thistles: Ortho 0204810
- Ability to kill actively growing thistles - 2,4-D, Mecoprop-p and Dicamba
- Kill weeds to the roots
- Cost-efficient & perfect for large areas – coverage of up to 64,000 square feet
- The handle design makes it a bit tricky to pour the product out
For killing and preventing actively growing thistles, you won't find any herbicide that's as effective as the Ortho 0204810.
Its active ingredients are three proven herbicides: 2,4-D, Mecoprop-p and Dicamba, which kill both the roots and leaves of thistles. These ingredients are absorbed into the plant, targeting the thistle's foliage and roots, which helps to prevent further growth.
Peace in mind, its formula is designed to not harm grass, as long as it is applied according to the directions on the label.
Each 1-gallon bottle of this product can treat up to 64,000 square feet, ensuring that you can cover a large area with one application.
|Ortho 0204810 Specifications|
2,4-D, Mecoprop-p and Dicamba
2,4-D, Mecoprop-p and Dicamba
Kill weeds to the roots
coverage of up to 64,000 square feet
Want an herbicide that can kill and prevent actively growing thistles? Check out the Ortho 0204810
How To Choose The best herbicide for thistles?
When selecting an herbicide for controlling thistles, the active ingredients to consider are glyphosate, metsulfuron, thifensulfuron, prosulfuron and clethodim.
Each of these active ingredients has different modes of action, making you understand each herbicide’s mode of action in order to select the proper one for a given crop.
Glyphosate is a non-selective, systemic herbicide that kills all vegetation, including grasses and thistles. This makes it an effective choice for controlling thistle, although it is not recommended for sites prone to soil erosion.
When using glyphosate to control thistles, you should also re-vegetate the area to prevent seedlings from re-infesting the area.
Metsulfuron and Thifensulfuron
Metsulfuron and Thifensulfuron are both Sulfonylurea herbicides, which are effective at controlling thistles in cereals.
Prosulfuron is another Sulphonylurea that can be used to control sow-thistles in maize.
Clethodim is an active ingredient found in many herbicides. It has been found to be effective at controlling most grass weed species, including hard-to-control grass weeds, such as bull thistle.
It is important to note that each of these active ingredients will have different effects on different crops, so it is important to read the labels carefully and select the correct active ingredient for each crop.
Additionally, some of these active ingredients may have other considerations such as environmental impact or potential injury to desirable plants.
Choosing the right volume of herbicide to use depends on three factors, including:
- Size of the area you're treating
- Type of herbicide you are using
- The desired rate of application
Size Of The Area You're Treating
To determine the size of the area that needs to be treated, you can measure it in square feet or acres, depending on the size. Then, calculate the amount of herbicide needed to cover the entire area.
Type Of Herbicide You Are Using
Different herbicides have different rates of application, so it's essential to identify the herbicide type you're going to use.
For example, glyphosate is typically applied at 24 to 32 ounces per acre (700 to 950ml), Atrazine is applied from 1 pint to 2 pints per acre (470 to 950ml), and many new multi-mode of action herbicides use 3 to 6 ounces per acre.
Once you've determined the rate of application for your herbicide, calculate how much herbicide you need for the area you're treating.
The Desired Rate Of Application
To decide on the volume of water you will use to mix your herbicide, follow this rule of thumb: 10mL of herbicide per liter of water.
Based on this guideline, calculate how much water you need to mix the required amount of herbicide.
Which Brands Make The best herbicide for thistles?
Green Gobbler is a reliable brand of herbicides. Their products are made from natural ingredients and do not contain any harmful chemicals.
Syngenta offers a wide variety of herbicides, insecticides, fungicides, and seed treatments, as well as genetically engineered crops that are tolerant to glyphosate, making it easier and more efficient for farmers to control weeds without damaging the crops.
They have a strong commitment to helping farmers grow safe and nutritious food while taking care of the planet.
Can herbicide permanently get rid of thistles?
Yes, herbicide can permanently get rid of thistles when applied correctly. Selective weed killers containing clopyralid or triclopyr are typically effective at killing thistles without damaging the surrounding plants.
What time of year do you spray herbicide for thistles?
The ideal time to spray herbicide for thistles is generally in April or May, when the plants are actively growing. Depending on the specific crop, these recommendations may vary.
What time of day do you spray herbicide for thistles?
The best time to spray herbicide for thistles is usually midday or midnight, when the sun is at its peak or when there is less wind and better coverage of the herbicide. This will help ensure that the herbicide is most effective in controlling the thistle population.
How many times a year should you spray herbicide for thistles?
For optimal effectiveness, you should spray herbicides for thistles at least two times per year, once in the spring and once in the fall. You should make sure to spray before the seeds have had a chance to begin growing and before they have set.
How long does herbicide treatment last?
The length of time herbicide treatment lasts depends on the type of herbicide being used, and can range from a few days to several weeks. Generally, broad-spectrum systemic herbicides will kill weeds and start to decompose within 14 days.
Thistles are pesky, persistent weeds that can quickly take over your garden. But with the right herbicide and a bit of know-how, you can easily get rid of them.
We have just walked you through all the pieces of information to choose the best herbicide for thistles for your needs. And hopefully, with these recommendations, you’ll have no problem tackling those pesky thistles!
Thanks for reading!