Extension Educator, Horticulture
Beaten, eaten, poked, smoked, scorned, but rarely mourned. At some time in our lives a weed will be on our hit list. However some weeds are more than just a "plant out of place".
Weeds at their worst can degrade natural areas and take over home landscapes to produce an unwanted one-plant show. Garlic mustard, Alliaria petiolata, has been the scourge of forested areas for years, but is now prevalent in gardens.
Garlic mustard is native to Europe where it hangs out in hedgerows, fencerows and open canopy woods. Here in the Midwest it loves the partial shade of our deciduous forests and backyard gardens where it can blanket the ground and smother other plants in its path.
As a cool season biennial, garlic mustard seeds germinate in early spring to form a rosette (bouquet) of kidney bean shaped leaves. In spring, usually starting the first of May, the mature plant sends up a 2.5-3 foot tall flower stalk with numerous small four-petaled white flowers. It's actually kind of pretty. This year with our warm March it started blooming in late March.
Plants set seed and the original plant dies; however, one plant can produce thousands of seeds. Just one year of seed production can produce a reoccurring nightmare of too much garlic.
The leaves of garlic mustard resemble violets, but garlic mustard leaves have more obvious veins and more deeply scalloped edges. Crushed leaves have a distinct smell of garlic except in late fall and winter.
Because of its ability to dominate relatively undisturbed forests garlic mustard is responsible for the decline of native plants and the insects and animals that rely on them. Not only does garlic mustard shade out other plants, but it also produces chemicals that can keep other plants from growing around it. It's definitely a bully biennial in the forest or the garden.
As with most exotic invasive weeds garlic mustard has no natural control here, even deer won't eat it. Research continues on biological control.
So what can you do to halt the spread of garlic mustard?
Control garlic mustard in your garden or woodland now. (Yes, right now.)
The key to garlic mustard management is early detection and eradication before plants flower. For pictures and information http://www.nps.gov/plants/alien/fact/pdf/alpe1.pdf
If you can't beat 'em, then eat 'em. Garlic mustard is reportedly high in Vitamins A and C. http://www.ma-eppc.org/weedrecipes.html
May is Invasive Species Awareness Month. Get involved in the Great Garlic Mustard Hunt. Visit http://web.extension.illinois.edu/cfiv/mn/3436.html for remaining dates and locations.