By DEBORAH BEHRENDS
Illinois Correspondent

ELGIN, Ill. — The area’s first Garlic Mustard Festival was at the Hawthorne Hill Nature Center in Elgin earlier this month. The festival attracted area residents, college students, parents and children who wanted to learn more about the invasive - but edible - plant.

Garlic mustard is a biennial plant brought to America from Europe. According to April Anderson, naturalist at Hawthorn Hill, Europeans used the plant as a poultice for bug bites and as a remedy for both eczema and asthma.

The plant has green leaves year-round, four white petals per flower and a garlic-like odor when the leaves are rubbed. It can grow to 3-feet tall in its second year.

One plant can produce anywhere from 350-7,900 seeds in one year. The seeds can survive in the soil for up to seven years.

The plant harms native trees, shrubs and plants such as Jack-in-the-pulpit, Virginia bluebells, marsh marigold, bloodroot, spring beauty, mayapple, toothwort and shooting star. Not only does garlic mustard smother toothwort, the plant on which butterflies lay eggs, but it’s toxic to the eggs.

New plants are emerging and second-year plants are flowering, spreading the seeds by the thousands.

“Anyone with undisturbed or natural areas around their home probably already know how invasive this weed can be to desirable plants,” said John Church, a University of Illinois Extension educator from Rockford, Ill.

Garlic mustard can be found in most places that are somewhat shady, whether in a home lawn, woodland, fencerow or wherever conditions are appropriate. It spreads rapidly and can invade in a relatively short time.

A biennial lifecycle means it completes its life over a two-year period. After the seeds germinate in the spring, the plant usually stays in the leafy rosette stage for the first year, appearing as a low plant of heart-shaped leaves, each about 2-8 inches in length.
The leaves also have irregular tooth margins.

In the second spring, the plant sends up a straight, slender flower stalk with small, white flower clusters of four petals each, which will develop seeds. Each plant produces thousands of seeds spread by wildlife, humans, water or other means.

Cutting and pulling plants before they set seed is one control method in smaller areas, but may be too labor intensive for larger patches.

After the Hawthorn Hill volunteers pulled the plants from the woods around the nature center, attendees went inside to sample how garlic mustard can be used to make salsa and pesto.

Controlled burns or herbicides may be needed in larger areas. Both should be used with care by knowledgeable people in a timely manner. Herbicide treatments work best in the spring and fall when the plants are actively growing. Be sure to read and follow all herbicide label directions and precautions before using.

For more information, contact a local University of Illinois Extension office, the Illinois Department of Natural Resources, Soil and Water Conservation District or other local park or forest preserve.