Garlic Mustard (Alliaria petiolata) may be an almost-attractive flowering plant, but it is actually an invasive species containing toxic chemicals, according to Plant Invaders of Mid-Atlantic Natural Areas.
This invasive was introduced by settlers coming from Europe for use as medicine and as a “flavoring agent in soups,” according to the Maryland Invasive Species Council (MISC).
However, the plant quickly spread and became harmful to native eastern U.S. plants and animals, according to a 2003 post on MISC’s web site.
The plant is a biennial herb in the mustard family, with leaves and stalks that change as the plant ages. Additionally, the book says that the “crushed leaves and stems smell like garlic,” presumably giving the plant its interesting name.
Garlic Mustard overtakes and impacts many plants, including wild ginger, bloodroot, and toothworts. When toothworts are taken over, three native butterfly species, the West Virginia white, the mustard white, and the falcate orange-tip, are greatly impacted, according to Plant Invaders.
This is because the chemicals in the plant are extremely toxic to the larvae of the native butterflies, which inhabit the toothwort plants. The butterflies feed on toothwort, and if their eggs are laid on Garlic Mustard instead, they will not hatch, according to MISC.
Garlic Mustard can occur not only in forest habitats, but also along roadsides and disturbed lands. However, according to the University of Maryland Home & Garden Information Center, the plant does prefer the shady environment of the forest and floodplain.
Management of Garlic Mustard takes a long-term effort, as the seeds can survive for over five years in the soil, according to Plant Invaders. The book says that hand removal can be effective for lightly scattered infestations of the plant, but suggests different methods for flowering plants with mature fruits.
So, if you want to see wildflowers and butterflies thrive, planting Garlic Mustard is not the wisest idea. Just make sure to eradicate it if the plant is already growing, because this intrusive plant will overwhelm anything nearby.
The "Invasive Species Spotlight" is a summer blog series focusing on a different plant each week that is a problem for Mid-Atlantic home gardeners.
About the author:
Jacqueline Hyman is a junior journalism and English major at the University of Maryland. She is the editor-in-chief of the Mitzpeh, an independent Jewish newspaper at UMD. In addition, Jacqueline enjoys musical theater, and teaches piano and voice at Guitar Center. She is excited to be interning this summer for the Washington Gardener.