This does not grow as well as the mustard, but tastes better and goes well in salad as a lettuce substitute. The stalks could also be used as a celery substitute, though they are generally a lot thinner and flimsier. I can’t remember where I got the seed from and I have a few old commercial seed packets. They require a bit more work. The soil should be turned over and mulched a bit, and they need more water.
Pak choy goes to seed in a manner very similar to mustard and the slightly larger seeds are also easy to collect.
Chinese cabbage (Brassica rapa, chinensis group; pinyin: báicài; Cantonese bak choi) is a Chinese leaf vegetable related to the Western cabbage. They are of the same species as the common turnip. There are many variations on its name, spelling, and Scientific classification. This is a common vegetable used in Chinese cuisine.
The Pekinensis group is the more common of the two, especially outside Asia; names such as da baicai (lit. "large white vegetable"); petsay/pechay (Tagalog); Chinese white cabbage; nappa, or napa, cabbage; and hakusai (Japanese) usually refer to members of this group. Pekinensis cabbages have broad green leaves with white petioles, tightly wrapped in a cylindrical formation and usually, but not necessarily, forming a compact head. As the group name indicates, this is particularly popular in northern China around Beijing (Peking).
The Chinensis group was originally classified as its own species under the name B. chinensis by Linnaeus. When used in English, the name bok choy typically refers to Chinensis. Smaller in size, the Mandarin term xiao baicai ("small white vegetable") as well as the descriptive English names Chinese chard, Chinese mustard, celery mustard and spoon cabbage are also employed. Chinensis varieties do not form heads; instead, they have smooth, dark green leaf blades forming a cluster reminiscent of mustard or celery. Chinensis varieties are popular in southern China and South-East Asia.
Commercial variants of Chinensis include:
The Ming dynasty pharmacologist Li Shizhen studied the Chinese cabbage for its medicinal qualities. Before this time the Chinese cabbage was largely confined to the Yangzi Delta region. The Chinese cabbage as it is known today is very similar to a variant bred in Zhejiang around the 14th century. During the following centuries, it became popular in northern China and the northern harvest soon exceeded the southern one. Northern cabbages were exported along the Grand Canal to Zhejiang and as far south as Guangdong.
They were introduced to Korea in the 15th century, where it became the staple vegetable for making kimchi. In the early 20th century, it was taken to Japan by returning soldiers who had fought in Manchuria during the Russo-Japanese War. At present the Chinese cabbage is quite commonly found in markets throughout the world.