Napa cabbage

Napa cabbage (Brassica rapa subsp. pekinensis, or Brassica rapa Pekinensis Group) is a type of Chinese cabbage originating near the Beijing region of China that is widely used in East Asian cuisine. Since the 20th century, it has also become a widespread crop in Europe, the Americas, and Australia. In much of the world, it is referred to as "Chinese cabbage".

The word "napa" in the name napa cabbage comes from colloquial and regional Japanese, where nappa (菜っ葉) refers to the leaves of any vegetable, especially when used as food. The Japanese name for this specific variety of cabbage is hakusai (白菜), a Sino-Japanese reading of the Chinese name báicài (白菜), literally "white vegetable". The Korean name for napa cabbage, baechu (배추), is a nativized word from the Sino-Korean reading, baekchae, of the same Chinese character sets. Today in Mandarin Chinese, napa cabbage is known as dàbáicài (大白菜), literally "big white vegetable", as opposed to the "small white vegetable" that is known in English as bok choy.

Outside of Asia, this vegetable is also referred to as Chinese cabbage or sometimes celery cabbage. It is also known as siu choy (Cantonese 紹菜), wombok in Australia and wong bok or won bok in New Zealand, all corruptions of wong ngaa baak (Cantonese 黃芽白). In the United Kingdom this vegetable is known as Chinese leaf or winter cabbage, and in the Philippines as petsay (from Hokkien, 白菜 (pe̍h-tshài)) or pechay baguio. Another name used in English is petsai or pe-tsai. In Ukrainian it is called pekins'ka kapusta (пекінська капуста), in Russian pekinskaya kapusta (пекинская капуста), and in Polish kapusta pekińska, literally "Beijing cabbage". In Sweden it is known as salladskål (salad cabbage) or sometimes kinakål (China cabbage).

The first records of napa cabbage cultivation date back to the 15th century in the Yangtze River region in China. From China it later spread to Korea and Japan. Beginning in the 19th century with the Chinese diaspora, it was distributed to the rest of Asia, Europe, America as well as Australia. During the 19th century napa cabbage was first introduced to America from Europe and the supply of seed materials from Europe continued until World War I. After the blockade of the European seed supply, US government research institutes and the seed industry developed new seed stocks for vegetable crops. Oregon and California were the cabbage seed production areas during that time. Today it is cultivated and eaten throughout the world.

Napa cabbage might have originated from natural hybridization between turnip (Brassica rapa subsp. rapa) and pak-choi (Brassica rapa subsp. chinensis). Artificial crosses between these two subspecies, as well as molecular data, strengthen this suggestion.

Napa cabbage is a cool season annual vegetable which grows best when the days are short and mild. The plant grows to an oblong shaped head consisting of tightly arranged crinkly, thick, light-green leaves with prominent white veins. Innermost layer leaves feature light yellow color.

Napa cabbage belongs to the family Brassicaceae, commonly called the mustard or cabbage family. It is closely related to other species in its genus Brassica, like broccoli, cauliflower, cabbage, and kale, as well as other cruciferous vegetables like arugula and wasabi. It is a different cultivar of the same species as bok choy and turnip.

The leaves, which are the harvested organ, lay side by side densely, are lime green coloured with white leaf veins and have a smooth surface. The vegetable has an oval form and weighs 1 to 3 kg (2.2 to 6.6 lb). The leaves are organized in basal rosettes. The flowers are yellow and have a typical Brassicaceae cross-linked arrangement, hence the name Crucifereae, which means “cross-bearing”. Because the plant is harvested in an earlier stage than flowering, normally the flowers are not visible on the field.^{[citation needed]}