or Japanese mustard spinach is a leaf vegetable. It is a variety of Brassica rapa, the plant species that yields the turnip, mizuna, napa cabbage, and rapini. It is grown commercially in Japan and Taiwan. It is a versatile vegetable that's cooked and eaten in many ways. The plant is also used for fodder in some Asian countries. The name 'komatsuna' means 'greens of Komatsu' in Japanese, a reference to the village of Komatsugawa in Edogawa near Tokyo, where it was heavily grown during the Edo period. It was named by Tokugawa Yoshimune, the eighth shogun, who visited Edogawa in 1719 for hunting and stopped at the localKatori Shrine for lunch. The shrine priest served him soup with a rice cake and a local leaf vegetable. The shogun was impressed by the flavor of the vegetable so much and named it komatsuna, after the nearby Komatsu River. Till this day, the Shin-Koiwa Katori Shrine offers komatsuna to the deities on New Year's Eve. People who come to the shrine to pray on New Year's Day are also given komatsuna for good luck in the new year. Since the days of the shogun, komatsuna has been bred to have a sweeter taste. The old variety thought to have been served to the shogun is not widely available. That variety is called Goseki bansei. It grows faster and has bigger but fewer leaves than ordinary komatsuna, and a strong, spicy flavor. The leaves of komatsuna may be eaten at any stage of their growth. In a mature plant they are dark green with slenderlight green stalks, around 30 centimeters long and 18 cm wide. It is most often grown in the spring and autumn, as it cannot endure extreme heat or cold for more than a short time. Although nowadays it's grown year-round in green houses.
Cooking
Komatsuna has a fresh, sweet taste and a crunchy texture. It's a very versatile vegetable and can be eaten raw, pickled, stir-fried, boiled, used fresh in salads, or added to soups. It's popular in soups as it can stay firm after being simmered. It is an excellent source of calcium, vitamin A, and vitamin C.
