"Vitamin-na" (Brassica campestris cv. Vitamin-na) belongs to Brassiaceae (the Mustard family). It is a biennial herb and a kind of "Tsukena (pickled vegetables)" cultivated at the Shimane Prefectural Agricultural Experiment Station in 1954. It is a hybrid of "Oosaka-shirona" and "Chinese flat cabbage", and is characterized by a high content of vitamin A. The leaves are dark green and soft, the bolting is slow, and it is an easy-to-cultivate variety with excellent cold resistance and disease resistance. It can be used for pickles, simmered dishes, soaked dishes, stir-fried oil, and miso soup. In 2003, they also produced a variety called "Asukko", which is a cross between "Vitamin-na" and "broccoli".