Plants of the Eloise Butler Wildflower Garden

Garlic Mustard is an introduced and naturalized biennial. First year plants form a basal rosette which flowers the second year when it raises an unbranched hairless stem that can be 4 inches to 4 feet high.

Leaves: The basal leaves are ovate to oval with a heart-shaped base, with very coarse teeth and a long stalk. Second year stem leaves are more triangular shaped with rounded lobes on the margins, tapering to a rounded point at the tip and a more truncate base tapering to a short stalk. The underside is paler in color with hair. The leaves produce a garlic smell when crushed.

The inflorescence is a short terminal raceme of stalked flowers. Clusters may also rise from the upper leaf axils. These racemes are short at first but like many mustard family plants, once flowers bloom, the raceme elongates as seed pods form below and flowers continue to open at the top.

Flowers are 4-parted, with a short calyx that has four whitish sepals with green tips and 4 white spatula like petals that have rounded blunt tips, claw-like bases and spread outward. Petals are longer than the sepals. Stamens number six in pairs, with one pair shorter than the other two. They have white filaments and yellowish anthers and there is a single short green style with a blunt tip rising from a green ovary that has multiple ovules. Nectar glands are at the base of the stamen filaments.

Seed: Garlic Mustard flowers very early in spring and continuously into summer and produces huge quantities of seeds which can lie dormant for years. The seed pods (siliques) are long and thin, with 4 angles, horizontal or upward pointing and contain a flat row of dark brown to black ribbed seeds that are attached to two sides of a central membrane in the pod. The seeds are oblong, up to 4.5 mm long x 2 mm wide, tapering to a sharp point. They will remain viable in the soil for 5+ years.

Habitat: Garlic Mustard produces a fleshy tough branching taproot, but spreads by re-seeding. It colonizes from an established area outward and if unchecked will cover vast areas, preventing growth of other plants. It easily moves into disturbed areas and woodland edges. It adapts to many soil types and moisture conditions except constantly moist soils. It prefers full sun, but does well in partial shade. It has no known pests and deer and other browsers avoid it.

Names: The genus Alliaria comes from 'Allium' for garlic or onion, and the Latin aria, meaning 'a connection' which all refers to the plant having a garlic odor when crushed. The species petiolata means 'with a leaf stalk', which differentiates this species from other Alliums which have leaves rising from the root or from a basal sheath.

The authorship of the plant classification is as follows: First to describe, in 1808 and assigning the name Arabis petiolata was ‘M.Bieb.’ who was Friedrich August Marschall von Bieberstein (1768-1826) German botanist and explorer who published several works on the flora of parts of Russia. His work was updated in 1913 by two others. ‘Cavara’ is Fridiano Cavara (1857-1929) Italian botanist who was director of the botanical garden in Catania Sicily and then director of the Naples Botanical Garden and ‘Grande’ who is Loreto Grande (1878-1965), Italian botanist who worked at the Naples Botanical Garden. In between these two classifications the plant was sometimes listed as Alliaria officinalis.