Invasive Species -


Garlic Mustard
(Alliaria petiolata (Bieb.) Cavara and Grande)


Photos & Description courtesy of IPANE

What Garlic Mustard does to the habitat

Garlic Mustard can colonize an area with breath-taking speed, and then competes for light and nutrients with native spring blooming wild flowers.


Garlic Mustard destroys a fungus in the soil that native plants need to get nutrients from the soil.


Garlic Mustard threatens several native butterfly species whose larva eat the native Mustard plants. Because the Garlic Mustard has become so abundant butterflies are placing their eggs on them, but the larva die because of incompatible chemistries.



If the soil is moist the plant may be pulled up with the root intact. If the plants have begun to flower they should not be left on the property as they will still disperse seeds.

If the area is too large for hand picking, you can cut them down to ground level in the Spring before flowers open (but not too early or they will send up a second flower) then apply Round Up in the Fall.

Since this is a biennial you get two whacks at it. The first year it produces a rosette. Learn to recognize it so you can get a jump on eradication.

Be aware the seed bank may live up to 5 years, so even though you have eradicated, you still have to be vigilant.


Be sure to get the plucked plants off your property in bags in the garbage. Any plants left around will come back in spades next year.


Common Name

Full Scientific Name

Garlic mustard Alliaria petiolata (Bieb.) Cavara and Grande

Family Name Common

Family Scientific Name

Mustard family Alliaria petiolata



Botanical Glossary

Alliaria petiolata is an herbaceous biennial whose flowering form can reach 1 m (3.3 ft.) in height. The first year plants are a basal rosette of leaves that remain green throughout the winter. They develop into mature flowering plants the following spring. The lower, dark green leaves are reniform (kidney-shaped), while the stem leaves are alternate and deltoid. The basal leaf blades can be 6-10 cm (2.4-4 in.) long and wide, while the stem leaves are 3-8 cm (1.2-3.1 in.) long and wide, gradually decreasing in size as they go up the stem. The margins of the leaves are coarsely toothed. The leaves give off a strong garlic odor when crushed. The flowers of Alliaria petiolata are consistent with those of the mustard family. That is, there are four white petals arranged in a cross shape, and these are 5-6 mm (0.25 in.) in diameter. The flowers are arranged in terminal racemes. They appear in the early spring (April-May), and fruits are produced by May. The cylindrical, shiny, black seeds are 3 mm (0.1 in.) in size and are contained in pods called siliques. These siliques are 2.5-6 cm (1-2.4 in.) long and 2 mm (0.08 in.) wide and contain 10-20 seeds. By June the plants are dead, often with the fruits still attached. Page References Gleason & Cronquist 197, Holmgren 180, Magee & Ahles 558.

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