It helps, of course, to identify a patch in the summer or fall so you will know where to clear away the snow when the plants are covered. At the end is a postscript on barks, roots, and sap. Be sure you have a good field guide to ensure proper identification and prevent consumption of poisonous species. Remember, when foraging, to pick less than one-third of a given patch to ensure the continued flourishing of the plant community. Remember too, to thank the plants for giving so generously of their hard-won growth.
Garlic mustard grows in open woods and at the edges of gardens, woods, and buildings.
Also, violet is a dark green with veins directed at the tip. Garlic mustard is paler, yellowish-green, with veins that meander across the leaf in a mosaic pattern. In winter, the dried stalk sometimes survives, with inch-long narrow pods sticking out from the sides. By midwinter most of the miniscule black seeds have been scattered, but if you find some, they will be pungent and useful as a cooking spice. Once you have located a plant that answers this description, crush a leaf between your fingernails and sniff.