This biennial grows in roadsides, hedgerows and woodland areas, but is less common in Scotland than it is in England, and is completely absent in the North West and Isles.
It has glossy, heart-shaped, bright-green leaves. The leaves are toothed along the edges like nettle leaves, and smell strongly of garlic when crushed. In fact all parts of the plant give off the pungent odour of garlic during spring flowering season. This is not to be confused with Wild Garlic (Allium ursinum) which is a bulbous perennial, member of the onion family, and has straight narrow leaves.
The stems end in a cluster of tiny white 4-petalled flowers about 6mm in diameter. Each flower develops into a straight square-sided siliqua, about 4cm in length, and containing 2 rows of small black seeds.
Alliaria, which means of the onion family, is incorrect nomenclature because it is actually a brassica, but petiolata, which means, in reference to the leaves, having petioles or stalks connecting leaf to stem, is correct. It also goes by the old folk name of Jack-by-the-Hedge.
This plant is edible, and apparently the young leaves are quite tasty in salads, if you like garlicy flavours. In the 17th Century it was used as a herbal accompaniment to salted fish. The leaves are an excellent source of Vitamins A and C.