Sometimes confused with wild garlic, wild onion is invasive and hard to stop once in your yard. Although it is a winter perennial, it sprouts up in the spring, March and April to be specific. It is a real pain to get rid of as you have to make sure to get ALL the bulbs when removing.
What is wild onion? What does it look like?
This winter perennial grows 8-12 inches tall with leaves that appear directly from the bulb. Both wild onion and wild garlic have thin, green, waxy leaves. But here's how to tell them apart - the leaves of wild garlic are round and hollow, and those of wild onion are flat and solid.
What you're really wondering is: I've got a yard full of "onions," can we make good use out of these annoying weeds and eat them? From our experts - we do not recommend it! According to research, you can eat wild onions. But that term applies to many varieties, and it takes someone who really knows what to look for and "smell for" to tell if the plant is edible. Bottom line is: don't do it.
How do you treat wild onion?
Pulling them up will get rid of them the fastest but is very labor intensive. If you have too much to pull up, you can treat with a post-emergent herbicide. Be prepared, this weed is persistent and will need to be sprayed multiple times. The thin glossy leaves make it difficult for the post-emergent to stick. Tip: mow your lawn, then apply the post emergent herbicide. It will stick better making the herbicide more effective.
How do you prevent wild onion?
Treat with a pre-emergent herbicide in November and again in late winter or early spring before these plants reproduce the next generation of bulbs. If you have a sizable infestation, you will be treating for a few seasons to completely get rid of it as bulbs can persist in the soil for years.
Here's an overview of wild onion:
Appearance: 8-12 inches tall with solid flat leaves that appear directly from the bulb.
Life Cycle: Winter annual, the leaves will die off once the heat of summer comes, but the bulbs will not. They stay dormant until the next spring.
Where it Grows: Lawn or gardens in sun or shade
Reproduces by: Bulb plants that reproduce by seed
How to Prevent: Treat with pre-emergent herbicide in November and again in late winter or early spring
How to Remove: Pulling them up carefully will get rid of them, and you may also have to treat with a post-emergent herbicide more than once to ensure all the bulbs are dead.