Bok choy, also known as pak choy or pac choi, is a leafy vegetable that belongs to the mustard family. It is commonly referred to as ‘chinese cabbage.’ Bok choy is a non-heading form of Chinese cabbage and has thick white or pale green leafstalks (petioles). Leaves are dark green in color but there are cultivars with red leaves as well. Chinese cabbage is a coolseason annual vegetable and is grown by a number of vegetable growers in the state. The crop grows best with short days and moderate to cool temperatures (60 to 70° F mean temperature). Higher temperatures lead to soft and bitter heads and often lead to seed stalk formation (bolting).
Iowa State University
Nair, Ajay; Jokela, Dana; Kruse, Ray; and Tillman, Jennifer, "Bok Choy Cultivar Trial for Spring High Tunnel Production" (2015). Iowa State Research Farm Progress Reports. 2157.