Orychophragmus violaceus aka Mustard

Orychophragmus violaceus is known as Chinese violet cress. It belongs to the mustard family, Brassicaceae. Its native range covers northern and eastern China to northern Korea. It grows in temperate regions across a wide range of sites. These include roadsides, fields, forests, thickets, and garden areas. It also grows in valleys and on hillsides and sunny slopes. Its habitats extend from near sea level into upland areas.

This plant grows as an annual or a biennial. Garden plants reach 1–2 feet [0.30–0.61 metres] tall and wide. The leaves form a rosette at the plant's base. They have a kidney shape, with lobes arranged along the midrib. Their edges have teeth, and their bases have a heart shape. Leaf colour ranges from rich green to blue-green. The stems bear much smaller leaves than the basal rosette. As plants grow larger, their stems tend to trail.

The violet flowers bloom from May to June. Their showy colour gives the plant value in garden beds. Gardeners can use it to edge beds or fill containers. It also suits herb gardens, where its edible parts have value. Growers in China raise this plant as a vegetable. They harvest the stalks in the second year, after flowering. The leaves and flowers can go into salads. Plants For A Future also records cooked leaves as food.

Grow it in average soil that drains well and stays moist. Full sun suits it, though the growing guidance allows part shade. Avoid deep shade, which the plant does not tolerate. It needs a moderate amount of water. Missouri Botanical Garden lists USDA hardiness zones 7–10. Plants do not survive winters with repeated temperatures below 20°F unless protected in a cold frame. In hardy areas, sow outdoors in late spring or early summer for biennial growth. Move seedlings to a sunny nursery bed after the second leaf pair forms.

Fall sowing offers another route, growing plants as winter annuals. Use a cold frame where winter cold prevents outdoor survival. Plants may reseed when garden conditions suit them. Missouri Botanical Garden reports no serious insect or disease problems. It lists a medium level of upkeep. Plants For A Future records no known hazards or medicinal uses. Its food-use rating is low, despite the documented edible parts.