Wild onion and wild garlic are both winter perennials that, when once established, can be difficult to remove. The leaves are waxy, upright and needle shaped growing 8" - 12".
Telling the difference between the two can be difficult, but if you can remember that the leaves of wild garlic are hollow and round and have a strong garlic odor. The leaves of wild onion are solid and flat and appear directly from the bulb. Both plants grow from underground bulbs.
The white to light green flowers of wild garlic develop on short stems above aerial bulbs. Wild onion does not have a stem; white to pink flowers with six eliptical segments. Both plants flower from April through June.
Bulb has reticulated (net like) membrane or covering.
Leaves occur from the base of the plant, and tend to be flat (not hollow).
Leaves are hollow, and tend to be formed higher on the stem (not where stem comes out of the ground).
Distinct garlic odor.
While these plants can easily be pulled from wet soil, they usually leave bulbs in the ground and will re-appear in short time. In fact, the garlic produces many underground bulblets that are difficult to remove even when the plant is dug up by a spade. Mulching can help prevent the emergence of these plants in the garden beds.
If you resort to herbicides, there are a few good options. Non-selective herbicides such as Roundup. Making sure to keep the spray off other plants. Selective herbicides for turfgrass include metsulfuron methyl (Manor®), imazaquin (Image), imazapic (Plateau), and 2,4-D. These herbicides can be used safely when the weed plants are growing in most turfgrasses. All of these herbicides appear to control wild garlic. Be certain to read and understand the herbicide labels before applying any chemical.
TIP: When using these herbicides, it is best to use rubber gloves and dip a small scouring pad sponge int the herbicide and rub the sponge up the length of the plant. This causes minute scratches and allows the herbicide to penetrate the waxy layer.