Bok Choy is also referred to as Pak Choi, Pak choy or non-hearting Chinese cabbage. It differs from hearting Chinese cabbage. Bok Choy leaves are harvested before the plant is fully mature, hearting chinese cabbage is not.
Planting Bok Choy
The best way to plant Bok choy is by direct seeding into a fertile, well-tilled garden bed. Follow seed package directions for spacing requirements as different varieties have differing requirements.
Transplants are also done, if you decide to transplant seedlings started indoors, set them out at the spacing's on the seed packet only after the danger of frost has passed.
Transplanting has been known to cause shock, which frequently leads to bolting. Be sure to harden the seedlings off to reduce the risk of transplant shock. Hardening means to Place them outdoors in their original containers where they will receive direct sunlight and some wind for a few hours each day for a week, possibly more. Gradually lengthen the amount of time outside each day. Move the plants inside at night.
Bok choy does well in cool weather, late spring and early fall, in temperatures of 50 F to 70 F. Warm weather has been known to cause it to prematurely bolt to seed.
For optimal results, sow seeds or transplants after the last frost day for your area. Bok choy can also be started indoors 4 to 6 weeks prior to the last winter frost, or for a late season harvest no longer than 1-2 months before the first Autumn frost. Once again 50 and 70 degrees f soil temperature for proper seed germination.
Bok choy when planted later in the season should receive full sun, but partial shade is best if in mid season for summer crops. 6-8 hours of direct sunlight dally is all it actually requires and stress is not uncommon under excessive light and heat. Stress not only leads to a substandard harvest but potential bolting as well.
Soil should be well drained, rich, loose and fertile with a Soil pH of 6.0 to 7.5. Ample mature compost is advisable prior to planting. Organic fertilizer heavier in nitrogen and less phosphorus is best after thinning or transplanting.
Bok choy requires ample moisture to thrive and prevent premature bolting. Keep the soil moist with regular, even watering, usually about an inch weekly. Use heavy mulch which helps moisture retention in the soil, repels some insects and suppresses weeds.
Harvesting Bok Choy
Most varieties of bok choy should be harvested while the plant is not fully mature, generally 12 to 18 inches in height, and as early as 6-8 weeks from sowing, although this varies slightly from variety to variety. Bok Choy grown hydroponically can be harvested in as little as 30 days. Harvest the entire plant instead of leaf by leaf. If the weather becomes excessively hot, harvest early .
You can also get multiple harvests from one planting. Cut just above the soil line when harvesting individual stalks. The roots still in the ground will produce a new head initiating from the center. After the first harvest the plant becomes less robust and the harvestable heads are not as big as the first - but hey two heads are better than one. After the third harvest the season is usually exhausted as is the plant.
Bok Choy Varieties
The primary difference between most types of bok choy is the head size. Smaller varieties are sweeter and more tender, while the larger, dark green varieties are more common among westerners. There are over 20 varieties of bok choy, with varying characteristics.
There are a number of Bok Choy varietes. Green stemmed, red leaf variations, as well as many that have the familiar white stem.
Red Bok Choy has deep violet oval shaped leaves and pale green stalks. The coloration pigments give a more mustardy flavor.
Napa cabbage is the most popular, it is not always recognized as an Asian vegetable as it is sold in non-Asian markets. It's a large oblong white stalked vegetable with pale green leaves that resembles romaine lettuce. Its mild taste and a soft texture makes it a favorite eaten raw in salads, but also works well in stir-fries.
Gai lan is not really Bok Choy but a close cousin, it is dark-green and more bitter if eaten raw. It is sometimes called Chinese Broccoli.
As with all members of the brassica family caterpillars love bok choy, spray every 10-14 days with Bt (Bacillus Thuringienis). Reapply if it rains. See: Cabbage Worms and Related Worms