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How to Kill Thistle In Your Garden

Do you keep on seeing thistle in your garden? Are you wondering how to kill thistle and fully be free from them? 

Did you know that they are the most stubborn type of weed? Thistles can be uncontrollable especially if you don’t get to catch them at an early phase. 

If you leave them there and ignore them, it will take you years before you can finally be able to get rid of them.

The good news is, there are numerous ways on how to kill these stubborn thistles for you to ensure that your garden will be free from weeds.

Get to know how to kill thistle by reading the information written below.


Here are some tips on how to kill thistle effectively:

Cutting the Thistle Down with a Sharp Tool

how to get rid of thistle

Once you notice that the thistles have already reached their full grown phase, you need to cut it at the base.

The weed will eventually pop back up, but if you continue cutting it often, the roots will start to experience stress, and the whole plant will start to wither.

You can either mow or cut the thistle every day for the first few weeks. This will not only help you get rid of the thistle but will also prevent it from start to dry out and start leaving any seeds.

Digging the Thistle's Root Down

Digging the root of the thistle using your hand

Source: Wikihow

The next thing that you can do is to start digging the root of the thistle using your hand.

But you should know that digging them out can be time-consuming since their roots are extended into the soil deeply and are spread wide.

If you get to remove the entire root, then you will be assured that the plant is gone forever.

If you have marsh and spear thistles, digging their roots out are ideal. The reason behind this is because their roots are not extensive, especially during their early stages.

So digging them out of the soil will help you remove them easier. Also, you need to make sure to pull as many roots as you can because broken roots have the ability to grow new plants.

Start Introducing Natural Predators

Certain insects and as well as mammals eat thistle

Source: Wikipedia

Certain insects and as well as mammals eat thistle, and if you start adding them to your garden, the thistle’s population will start to get under control.

This will make the thistle start feeling stressed again, and it will eventually stop from growing.

Some of the insects that are known to eat thistle are the yellow star-thistle hairy weevil, yellow star-thistle bud weevil, stem mining weevil, flower weevil, thistle stem gall fly, thistly rosette weevil, and the thistle head weevil.

Some of the animals that can eat thistle include, ponies, sheep, llamas, donkeys, and goats. For poisonous species, the cattle can take good care of them.

Using Non-Selective Herbicide

Another thing that you can do to kill thistle is by using a non-selective herbicide. But you should know that the vegetation in that area will also die. This is the reason why this method should be used only if you have a massive thistle infestation.

It is best to apply the non-selective herbicide during the active growth season, including fall and spring time. It would also be best to use them during hot sunny days to help kill the weeds immediately.

Asking for Professional Help

Asking for Professional Help

If you are having trouble killing the thistles due to their quantity, then you need to hire a professional to assist you with the problem.

The reason behind this is because the professional companies today are using powerful exterminations to ensure that thistles will be killed.

If you are planning to burn the thistles, asking for a professional to do this is essential as well, for you to avoid burning the other types of plants that you have in the garden.

Preventing the Appearance of Thistle In Your Garden

Of course, once you have killed the thistles, it would be best to make sure that they won’t be able to grow back again. Here are a few tips on how you can do that:

Growing Your Plants Closer Together

Limit the free space where the thistle can grow

To ensure that there will be no rooms for the thistles to start from popping out of your garden.

The reason why planting them closer together is important, and that is because it will limit the free space where the thistle can grow.

Removing Buds and Any Flowers

If you can’t mow down all of the thistles, you can start cutting all the new flowers and buds that are still unopened.

The reason why cutting is essential is that it will prevent the weeds from starting to seed. Always remember that if they cannot see, they won’t be able to start spreading.

Spreading Mulch in the Soil

After cutting the thistle or if you just want to stop the weeds from growing entirely, then spreading mulch over the ground is essential.

You need to make sure that you are covering a heavy layer to keep the sunlight from penetrating in the soil.

Without the sunlight, the thistle won’t be able to thrive and sprout. When mulching, it would be best to consider using pecan hulls, shredded wood chips, and as well as pine needles.

Creating a Cover Above the Soil

Providing a shade can help in killing the thistle

As mentioned above, thistles are thriving under the sunlight and providing a shade can help in killing the thistle.

You can start planting trees that can shade the area, but while waiting for your trees to grow, you can temporarily build a shelter.

The shelter will make sure that the area will be protected from the sunlight.

Wrapping Up How to Kill Thistle

Start killing the thistles now for you to be able to enjoy the beauty of your garden even more. These are the ways on how you can prevent the thistles from coming back into your garden. 

It would also be best to follow the tips above on how to kill thistle, for you to finally get rid of the weeds in your garden.

About the Author Ann Katelyn

I'm Ann Katelyn, Creator and Chief Author of Sumo Gardener. Since I was a child I've always been fascinated with plants and gardens, and as an adult this has developed into my most loved hobby. I have dedicated most of my life to gardening and started Sumo Gardener as a way to express my knowledge about gardening with the hope of helping other people's gardens thrive.

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