Pesky wild onions!

Asked May 8, 2019, 3:56 PM EDT

May years ago, I received a load of topsoil to help with my shrubs, etc. around my home in Oswego, NY. Oswego County is nationally known for its production of onions, and I think the topsoil I received was from "the muck" where those products are grown. The landscaping on south face of the home - in full sun - is overrun with wild onions EVERY YEAR. I've tried carefully digging them out to no avail. I tried a commercial weed killer and the weeds came back, Plus I must have accidentally sprayed some on the new shrub, because it's dead now. I'm afraid to apply another weed killer that goes to the roots because I don't want to destroy a beautiful dappled willow that is very happy there. Suggestions on how to get rid of this nuisance?

New York County New York

4 Responses


The only organic route to getting rid of these (and we are with you on preferring a non-toxic solution) is plucking them out, being certain to get the bulb. You can also improve the quality of the turf, as wild onions prosper in lawns that are low in calcium, high in potassium and poor in drainage. Add calcium and gently fork in a half inch of compost over the area.

Thank you so much for responding so quickly. I spent a number of hours digging up wild onions yesterday, so your advice was exactly what I did. I will not use the weed killer again. The expert at the lawn and garden store also suggested white vinegar (diluted slightly). Have you ever heard of that working on weeds, and perhaps this wild onion.
I also have an issue with the fella who puts fertilizer, weed killer, etc on my lawn. Why is it that no one takes a soil sample to see what nutrients the lawn really needs? And - I've had no luck finding anyone here in Oswego County who offers soil test kits. Do you think determining the pH of the soil is important? I own a pool and favorable pH is sure necessary for the pool chemicals to work effectively ! Thank you again! (Should I have posted this as a separate question?)

I have heard of using a vinegar solution to kill weeds but it will affect the grass as well. Both are most likely to slowly die back above ground and then re-grow from the root. This kind of solution is usually used for weeds in a pathway or another space where nothing should be growing.

I do recommend having your soil tested by a lab. Improper pH is not what is causing the onions to proliferate, but it is an important factor in the health of all plants. If you contact your Cornell Cooperative Extension of Oswego County in Mexico NY, or 315-963-7286, they should be able to tell you how to have your soil tested. Many county cooperative extensions in NY have their own labs and those that do not refer soil tests to nearby counties or outside labs.

I am SO APPRECIATIVE of solid advice from someone who is not just selling their own product !! THANK YOU !!!! And the response time has been phenomenal. When I get my lawn to look like the 18th fairway at Augusta during the Masters Golf Tournament, I'll (finally) be happy about my grass. Thank you again for the great information.