Cover vegetables. Mustard is a herb of Cruciferae. Its plant height is between 40 cm and 150 cm, and its leaves are green with bristles and frost. Taizhou mustard, also known as cabbage, is cultivated all over China. Salt leaves are edible; Seeds and whole herbs can be used as medicine to eliminate phlegm, relieve asthma, reduce swelling and relieve pain. Seed powder is called mustard and used as seasoning. The pressed oil is called mustard oil, which is an excellent nectar source plant.