Wild onion grass


Have wild onion overtaking my south facing lawn. Spreading through lawn and into flower bed. Very deep rooted with small onion bulb when dug up. How can one get rid of i?


Although wild onion is cultivated and is considered a delicacy by gardeners, especially those interested in permaculture, when it is spreading through your lawn and into your flower beds, it is a plant in the wrong place.  The Ontario Ministry of Agriculture, Food and Rural Affairs has advised us as follows:

As wild onion is a weed that is not on the Ontario’s Noxious Weed list you are limited to how to control it, with the Cosmetic Pesticide Ban administered by the Ministry of Environment, Conservation and Parks.   Should you wish to consider this route, this government site provides a list of pesticides that are available to homeowners in Ontario here.

Otherwise, you can try the following options, which will require persistence, but will eventually deplete the population:

  • dig them up especially before they go to seed
    • you will likely need to do this more than once a season and for more than one year
    • remove the entire plant including all the root (may work best for young plants)
    • don’t put the plants, roots or seeds in a compost as they may survive and spread when the compost is used(dispose of in landfill)
  • cut them then cover the area with landscape fabric or thick black plastic and a few inches of mulch to help prevent regrowth –you may need to leave this on for more than a year – for weeds that spread underground, several years might be necessary and also they may spread out under the uncovered edges
  • remember that any seeds in the soil can germinate after removal of plants so check back to remove any young ones as they start