Garlic mustard ... invasive weed. Yank it out by hand. Do not let it flower and seed.

Garlic mustard is very invasive. When you pull it, put it in a black bag and let it sit in the sun and cook a bit to be sure that the plants are really dead.

and just so you know, the term invasive refers to nonnative plants that spread via seed through wind or water or critters to outcompete and replace native plants.

It grows along a path in the sunny spots in our city park, it's pretty there, tall and airy in groups.

@NHBabs z4b-5a NH Et al. I read a little about Garlic Mustard. Apparently it has a five year growth cycle? Is that because its initial growth (as a seedling over the first several years) does not produce strong enough roots that one is unable to remove them and so it takes a period of five years for this non-native plant to be removed?

Also, I've noted Garlic Mustard on either side of our property on our neighbors' yards... what to do?

I don’t know what the 5 year life cycle refers to, and I would check the reliability of the source before believing it. One strategy I use for finding more reliable, scientific sources, is to use the scientific name, in this case Alliaria petiolata. Then I check the URL. Botanic gardens, state DNRs, and universities will be more reliable than something like a backyard gardener’ blog generally speaking.

IME it grows a rosette of leaves and then shoots up a flower stalk, sometimes the first year and sometimes the second, depending on when it sprouts and growing season length. I try to pull before it flowers, especially during times the soil is moist so I can get more root.

IME the seed has a long life in the soil, so you will always need to be vigilant. Learn what the small seedlings look like and smell like so you can pull them as soon as you see them. It may take more than 5 years of keeping an eye out because any time the soil is disturbed (planting, critters like chipmunks, voles, etc) there is the potential for deeply buried seeds to be brought to a better spot for sprouting.

Re the neighbors . . . Educate them to see if they will get on board. If not, you will need to be especially vigilant near your borders.

Well I guess you can always eat it. https://freakofnatural.com/garlic-mustard/

Humans have a tendency to villainize some plants, but so often they have over looked or unknown qualities.

One can eat many plants ... it doesn't really make them desirable unless you're planting something to eat. Japanese knotweed is edible, too ... and still an annoying, invasive weed in my garden and yard. If garlic mustard stayed put, it wouldn't be nearly so reviled. It's negatives simply far outweigh any positives. If you really desire to eat it, grow it in a pot, and still don't let it seed.

BlueberryBundtcake - 6a/MA I had no idea Japanse Knotweed was edible, interesting! I just googled it and actually found recipes...amazing.