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How to Kill Onion Grass? (And Prevent Growth Of Onion Weeds)

Every time that a person mows their lawn, they can notice that not everything is going as it should be, and basically, they notice something different there. That different thing is called “onion grass” which is quite different from the normal lawn that we are used to seeing and it needs to be removed from wherever you may see it!

In this article, I will be concluding with some of the main ways how any of you can kill onion grass, in order to have your lawn in the most perfect way possible!

Without further ado, let me get this article started!

What is Onion Grass?

Onion grass, else way is known as wild onion, is a type of grass that is seen in between a normal lawn. However, if you think deeply about it, it doesn’t do any harm, but still, it has to do a lot with the way that a specific lawn looks, and that is the reason why many people get rid of it.

It is definitely a very weird type of grass that will completely destroy the looks on your lawn or wherever it appears!

How to Notice Onion Grass?

In order to notice that there is onion grass on your lawn, you will first find out that it has a different smell and also a super different look. Onion grass is super tall when compared to normal grass, and it has super thin leaves with bell-shaped white flowers on the top.

Most of the time, you will find onion grass during the summer and autumn seasons, as the seeds move around your lawn, and find different places to lean on. I say lean on because the seeds of onion grass come from the flowers on the top of them, and if there is wind, wherever they stay, that is the place they appear.

How to Kill Onion Grass?

In order to fully get rid of onion grass, you should always think about two methods, physical (mechanical) and chemical. They are easy methods to be done, but still, when it comes to the chemical ones, it is definitely better if you have an idea about them.

Now, these are the methods or the ways that you can kill out onion grass out of your lawn:

Move it Out

The simplest physical way of getting rid of onion grass is by moving it out while using your hands, a shovel, or whatever would help. While doing this thing, you should be aware of the fact that you should pull it out with its complete roots because if any piece of the roots stands on the soil, then you will have to deal with onion grass again.


When I say water, I don’t mean normal water that we use to water different plants, but instead, you should use hot boiling water, as it is one of the most traditional methods of getting rid of different plants, bad and good ones as well. Boiling water will definitely kill any plant. However, if you do so, and use boiling water, you should take care of the entire plant, and not leave behind anything. If you see that any part of the roots hasn’t been destroyed, it would be better if you use water again, until nothing is left out.


Whenever you search for a particular killing of any particular plant, you will notice that the best thing to use when it comes to chemical substances is herbicides. They are substances that are used specifically for these types of things, and it is one of the methods that will surely and securely help you kill plants of any kind.


Even though it is not a permanent solution, mowing onion grass is considered a choice of getting rid of them as well. Anyways, when you mow them, you basically cut them, and that’s why it is not permanent. You should never expect to kill them all when using a mowing machine or mowing them with anything else, it is completely a temporary choice.

Frequently Asked Questions

Can one use vinegar? Will vinegar help you?

The use of vinegar is a little bit the same as the method of using boiling water for plants. It would kill any other plant, but when it comes to onion grass I wouldn’t advise you to use it since it will do nothing!

Where does onion grass appear?

Onion grass is a weird thing and it can appear everywhere, but its most loving environment is the acidic soil. So, if you use this type of soil in order to plant anything, it is a fact that you should wait for the onion grass to come alive.

Are wild onions and onion grass the same?

As mentioned at the beginning, onion grass has different names and one of them is wild onions. That concludes the fact that wild onions and onion grass are basically the same things.

Final Words

Coming through the end of this article, I would like to mention again that onion grass is not a dangerous thing to grow on your lawn or next to your plants, it won’t cause damage to anything, besides the fact that it may lose the beauty on the things. Just as already mentioned, people simply want to get rid of it because it doesn’t look good!

However, I really hope that this article and the methods that I mentioned will help you guys get rid of onion grass and kill it for once!

Further Reading

Here we came to the part of my article that I love most, and it includes giving advice of any kind to you! It is quite important to know how to kill a plant if you want to, but I think that the revival actions are one step further as a damaged plant can really make a plant owner feel bad! That’s why I will mention for you some “revival articles”.

In case you have a dying conifer plant, you can check out the ways how to revive it, or if you have the problem of dying with your money plant, I would gladly introduce you to my article regarding how to revive a dying money plant! From the money plant, I would like to mention the rescuing manners of a prayer plant, since I’ve seen that many people own it.

Hydrangea is an amazing type of flower but it has a bad thing and it is that it goes down quickly! However, there are ways on reviving a dying hydrangea that I would like to include for you!

Have fun!

Natalia Michalska

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