How to Destroy Wild Onion Plants

Overview

Wild onion plants (Allium canadense) are considered perennial weeds that are surprisingly in the lily family. Despite their name, they are not edible; they are, in fact, poisonous. However, when mowed, the plants let off an onion aroma, hence the name. Wild onion plants have bulbous roots that self-propagate year to year and can become invasive over time, especially in lawns. Wild onion plants pop up early in the spring and grow faster than grass.

Step 1

Wait until the early spring before your grass needs its first mowing and when the onion plants are about 6 to 10 inches tall.

Step 2

Select an herbicide that is appropriate for the site where the wild onion plants are growing. For instance, use an herbicide that is safe for lawns (e.g., 24,D ester) if the wild onions are in your lawn.

Step 3

Add in a spreader sticker--also called a surfactant--with the herbicide if the label calls for it. Follow the dosing instructions on both the herbicide and spreader sticker, since they come in varying strengths. In general, for a spreader sticker that is labeled with a volume mix of .50 percent, use 1 tbsp. for every quart of herbicide.

Step 4

Spray the wild onion plants. The spreader sticker helps the herbicide adhere to the plants. Reapply the following year at the same time for long-term success.