The garlic aroma of crushed or mowed leaves readily identifies this introduced weed. Wild garlic (Allium vineale) is found throughout the eastern United States and as far west as Colorado, with localized infestations on the West Coast. In the warmer parts of its range, the dark green grasslike shoots appear in the fall, elsewhere by early spring. The slender leaves are hollow and nearly round in cross section. This distinguishes wild garlic from wild onion (Allium canadense), a native whose leaves are flat and solid. Wild garlic can flower, producing umbels of greenish white, pink, or reddish purple flowers, but more often produces aerial bulblets. These, along with underground bulblets, are its principal means of reproduction. The bulblets do not all sprout at once, having varying lengths of dormancy from one to five years.
SYMPTOMS: Wild garlic growing in lawns is very conspicuous, particularly with warm-season grasses, which go dormant in the fall and winter. Left undisturbed, wild garlic stems can reach three feet by early summer, although the stress of regular cutting results in shorter, more slender foliage.
CONTROL: Small infestations can be pulled out by hand, especially when the soil is moist. Use a flat-tipped screwdriver or other tool to loosen the soil around a clump. Then, grab the base of the foliage and slowly tease it out of the ground, trying to remove as many of the bulbs as possible.
“Three-way” herbicide mixtures that contain 2,4-D, MCPP, and dicamba will kill both wild garlic and wild onion. Use the ester formulation of this three-way mix during the winter (check the label). Once nearby ornamentals have leafed out, however, switch to amine formulations which are less volatile at high temperatures and hence less likely to injure nontarget plants.
Imazaquin (Image) can also be used on certain dormant warm-season lawns and as a selective herbicide in some ornamental plantings. Consult the label for listed uses.
Finally, maintaining a healthy, dense turf devoid of thin, open areas will reduce opportunities for wild garlic to spread, as will regular cultivation and mulching of bare ground.