Winter-cress, yellow rocket

Barbarea vulgaris, the yellow rocket or winter-cress, is a biennial to short-lived perennial in the family Brassicaceae growing to about 80 cm tall and 25 cm across. It forms a basal rosette of glossy, dark-green, lyre-pinnatifid leaves with a large terminal lobe and smaller lateral lobes; the stem leaves are simpler, ovate, toothed or lobed. The ribbed, hairless stems branch from the base and bear dense terminal racemes of bright yellow, four-petalled flowers 7–9 mm long from April to July, followed by slender siliques 15–30 mm long. Native to Eurasia and North Africa, it favours moist roadsides, riverbanks, arable margins, ditches and waste ground from sea level to about 2,500 m on siliceous, calcareous, sandy, alluvial or clay soils, and is now naturalised as a weed across North America and New Zealand. The young leaves and flower shoots have a hot, cress-like flavour and have long been used as a spring potherb.