Wild Onion plague - Ask Extension
We have a continuing problem with clusters of wild onions invading large swaths of our grass and our flower beds. Our gardening service says they cann...
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Wild Onion plague #926607
Asked March 23, 2026, 5:36 PM EDT
We have a continuing problem with clusters of wild onions invading large swaths of our grass and our flower beds. Our gardening service says they cannot deal with wild onions. They are impossible to dig up--we have tried for years, but tiny bulbs stay in the ground and come back. Soon, our lawn will only be onions and no grass. Is there anything that can be done? We don't see them in other yards, for the most part. I am also afraid they will spread to our neighbor.
Montgomery County Ohio
Expert Response
Hi Vivian, wild onions and garlic are very difficult to control. That is probably why the lawn service didn't want to tackle them. The literature I discovered suggests digging them up using a spade to get below the bulbils and get all of them that are attached. That is a challenge to go over the whole yard. It can be done if you are persistent.
Next, you can use chemicals to control them. As you probably know, onions and garlic have a leaf with a waxy like coating that sheds water and herbicide. They used to recommend taking a heavy rubber glove and putting on another cotton glove that you dip in glyphosate (Roundup). That means that you are coming in very close contact with the chemical which is difficult to control. Then you grab the plant and essentially abrade the leaf surface and deposit the chemical on the abraded leaf. Back breaking deal for sure.
The glyphosate spray will kill everything. It usually has a spreader-sticker in the spray that makes it stick to plant leaves so that it will be absorbed. The downside to that is that any overspray will kill the grass around the target and you will have brown spots all over the place where the grass was killed until it fills in again.
Here is a fact sheet from PA: https://extension.psu.edu/wild-onion-and-wild-garlic . They suggest some chemicals that you might try to find. Most are labeled for turfgrass - meaning like a golf course where you can restrict traffic from going on the turf. I see that sulfentrazone is available at Walmart for instance. Some of these are restricted to commercial applicators. You must use PPE with rubber gloves and boots and proper attire. The key to chemical application is to apply the products consistently and keep at it. There is also a combination of the old standard 2,4D for broadleaf weeds and added dicamba. Again, this is a chemical that will kill a lot of weeds. It needs an adjuvant or spreader-sticker to get the product to stay on the leaves and be absorbed by the plant.
You might try another lawn service company that will come back several times. They don't want to get that much involved with it usually. If you do go with chemicals, again put on the PPE and wash or dispose of them after each application. Hope this helps you. Don
Next, you can use chemicals to control them. As you probably know, onions and garlic have a leaf with a waxy like coating that sheds water and herbicide. They used to recommend taking a heavy rubber glove and putting on another cotton glove that you dip in glyphosate (Roundup). That means that you are coming in very close contact with the chemical which is difficult to control. Then you grab the plant and essentially abrade the leaf surface and deposit the chemical on the abraded leaf. Back breaking deal for sure.
The glyphosate spray will kill everything. It usually has a spreader-sticker in the spray that makes it stick to plant leaves so that it will be absorbed. The downside to that is that any overspray will kill the grass around the target and you will have brown spots all over the place where the grass was killed until it fills in again.
Here is a fact sheet from PA: https://extension.psu.edu/wild-onion-and-wild-garlic . They suggest some chemicals that you might try to find. Most are labeled for turfgrass - meaning like a golf course where you can restrict traffic from going on the turf. I see that sulfentrazone is available at Walmart for instance. Some of these are restricted to commercial applicators. You must use PPE with rubber gloves and boots and proper attire. The key to chemical application is to apply the products consistently and keep at it. There is also a combination of the old standard 2,4D for broadleaf weeds and added dicamba. Again, this is a chemical that will kill a lot of weeds. It needs an adjuvant or spreader-sticker to get the product to stay on the leaves and be absorbed by the plant.
You might try another lawn service company that will come back several times. They don't want to get that much involved with it usually. If you do go with chemicals, again put on the PPE and wash or dispose of them after each application. Hope this helps you. Don
