Bok Choy, An Asian Staple
Brassica rapa subsp. chinensis
Family: Brassicaceae
COOL SEASON ASIAN VEGETABLE
These green varieties do not form heads and have green leaf blades with lighter bulbous bottoms instead, forming a cluster reminiscent of mustard greens. It has a flavor between spinach and water chestnuts but is slightly sweeter, with a mildly peppery undertone. The green leaves have a stronger flavor than the white bulb.
Other than the ambiguous term "Chinese cabbage", the most widely used name in North America for the chinensis variety is simply bok choy (Cantonese for "white vegetable") or siu bok choy (Cantonese, for "small white vegetable"; as opposed to dai bok choy meaning "big white vegetable" which refers to the larger Napa cabbage). It can also be spelled pak choi, bok choi, and pak choy. In the UK and South Africa, the term pak choi is used. Less commonly, the descriptive English names Chinese chard, Chinese mustard, celery mustard, and spoon cabbage are also employed.
In Mandarin Chinese, the common name is 青菜 qing cai ("green vegetable") or 小白菜 xiao bai cai ("small white vegetable").
Bok choy is native to China, originally from the Yangtze River Delta, where it has been cultivated for thousands of years. In the 14th century, Bok choy was transported via trade routes to Korea during the Joseon Dynasty, where it would become a key ingredient in kimchi. It was later introduced to Southeast Asia in the 16th century and Europe and North America in the 19th century via Chinese immigrants. Today Bok choy is still widely cultivated across Asia and Southeast Asia, and it is also grown and sold at farmers markets and specialty grocers in Australia, South Africa, Europe, Canada, South America, the Caribbean, Central America, and the United States.
USES
Bok choi cooks in 2 to 3 minutes by steaming, stir-frying, or simmering in water (8 minutes if steamed whole). The leaves cook more quickly than the stem. It is used in similar ways to other leafy vegetables such as spinach and cabbage. It can also be eaten raw. They are commonly used in salads.
PRESERVATION
Bok choy is often used to make numerous pickled food, including the most popular kimchi. Kimchi can be simple with mostly only bok choy, or it can have a multitude of ingredients. Bok Choy is fermented in several other ways and sometimes dried afterward, usually for use as soup stock and flavoring.
GROWING
SEASON & PLANTING
This is a cool season crop and seeds can be planted as early as September, and throughout the cool season. Plant starters can also be planted as soon as they are available in the nurseries. These plants grow relatively fast and several crops can be planted in a season.
SOIL & NUTRITION
Plant in well-amended garden soil. Feed throughout the season with a general purpose organic fertilizer.
TEMPERATURE & SUN EXPOSURE
Plant in full to part sun. Bok choy doesn’t seem to mind our brief cold snaps. It is said that temperatures below 32°F harm plants, but that doesn’t seem to be the problem where we live because the period when it is that cold is so brief. It takes sustained colder temperatures to damage the plants. At worst, if it gets cold enough, the outer leaves will turn brown. But the rest of the plant is usually fine.
WATER
Provide steady, regular water, as usually found in a garden bed.
HARVESTING
You can harvest outer leaves one at a time, as needed, or you can wait until plant forms a full open head and harvest the whole plant.
WILDLIFE
With warmer weather, noctuid moth larvae may eat holes in the leaves, which is purely cosmetic damage.
INVASIVENESS
Bok choy does not seem to escape cultivation in our region.
VARIETIES
Bok choy comes in a wide variety of form and color. The classic bok choy gets 2’ tall, and is fairly large. It usually has white stems and dark green tops. There are numerous smaller/dwarf varieties that grow only about 5” tall. Some varieties are all a lighter green color (including the stems). There are also varieties with purple leaves, and/or purple stems. Tatsoi is a different variety of Asian greens but looks like a flat-growing bok choy.