Brassicaceae: Alliaria petiolata

Files

Family Name

Brassicaceae

Common Name

Garlic mustard

Description

Alliaria petiolata is a biennial herb growing up to 1 m tall, with generally simple, unbranched stems that ate smooth or with a few short hairs. The simple, alternate, petiolate leaves are kidney shaped at the base and become deltoid toward the top, 3-6 cm long and wide with longer petioles at the base and short ones toward the top. The blades are shiny green, hairless or somewhat hairy and the margins are toothed. The leaves smell like garlic when crushed. First year plants consist of a rosette of small round to kidney shaped leaves with scalloped edges. The inflorescences are round clusters of a few to several white flowers. Each flower has 4 small green oblong sepals generally < 5 mm long, 4 white petals 4-8 mm long and 2-3 mm wide forming a cross. The fruit is a linear silique, 4-6 cm long. Garlic mustard blooms from April into June in disturbed areas, along roadsides in and open woods. It is a recent invader in South Dakota being found along the south and eastern borders.

Horticulture Notes

Garlic mustard is a very aggressive invasive weed and should be eradicated when encountered.