Long a staple in Asian cuisine and embraced within traditional Chinese medicine, bok choy — also known as bok choi, pak choi or pak choy — is now recognized worldwide. This green leafy vegetable closely related to cabbage is characterized by large lettuce-like leaves on top and creamy, celery-like stalks on the bottom. Bok choy leaves are smooth and tender, with a flavor somewhere between cabbage and chard.
The entire vegetable is edible, and when served raw or lightly blanched, bok choy adds a satisfying crunch to salads, stir-fries and soups. Koreans love to ferment bok choy with daikon radish, garlic, ginger and scallions to make a traditional spicy side dish called kimchi. Others enjoy shredded bok choy as a coleslaw. It is also delicious when sautéed with ginger and garlic.
While you will likely find it and other varieties of Chinese cabbage in your local grocery store, you may want to try growing your own. Because bok choy matures quickly and regrows easily, you won’t regret the time spent cultivating this tasty, nutrient-dense vegetable.
How to Recognize Bok Choy
Bok choy (Brassica rapa) is a type of Chinese cabbage related to other cruciferous vegetables like broccoli, cabbage, cauliflower and kale. Bok choy is characterized by broad green leaves flaring outward from an upright head. Its stalks, which resemble a fatter type of non-string celery, can be either green or white. Bok choy flower stalks emerge from the center of the plant during warm weather and can shoot up to be twice the size of the plant.
Similar to broccoli, bok choy flower stalks are characterized by brilliant yellow clusters resembling the ribs of an umbrella. The appearance of flower stalks may indicate the end of life for this cool-season vegetable. Flowering also signals the arrival of tougher, more fibrous leaves, a bitter aftertaste and, eventually, the end of the leaf harvest.
That said, some find the flower stalks to be tasty, suggesting these tender shoots possess a flavor similar to broccoli rabe. The size of mature bok choy plants depends on the variety grown. Typically, baby bok choy is less than 10 inches tall, with a stalk diameter of about 2 to 4 inches. Standard (or large) bok choy varieties reach 1 to 2 feet tall and have an average stalk diameter of around 6 inches.
Getting Started With Bok Choy
- Bok choy is a biennial and somewhat winter hardy
- When covered, it may survive in U.S. Department of Agriculture hardiness zones 4 to 7
- As a cool-season crop, bok choy will quickly flower and bolt to seed when temperatures warm up in the spring
Soil: Bok choy will flourish in well-draining soil with lots of rich, organic matter. If your soil is lacking nutrients, use an organic fertilizer high in nitrogen. While bok choy can survive in a soil pH ranging from 6.0 to 7.5, a pH in the 6.5 to 7.0 range is ideal.
Sowing indoors: To get a jump-start on the growing season, start bok choy seeds indoors about four to five weeks before the last expected frost in your area. Plant seeds one-half inch deep, spaced 1 inch apart. Bok choy seeds germinate quickly, usually within four to eight days.
Sowing outdoors: You can direct seed bok choy outdoors, in containers or your garden bed, beginning one to two weeks before the date of your last expected frost. The planting instructions for indoor sowing also apply outdoors.
Sun: While bok choy can handle full sun, it will thrive in partial shade. So, plan for your plants to receive three to five hours of sun daily. In summer, partial shade can prevent your plants from premature bolting.
Thinning: For best results you will want to thin plants when they have a couple of inches of growth. For full-sized bok choy, thin to allow for at least 6 to 8 inches of spacing between plants. The thinned plants are edible and will be tender and delicious, so be sure to eat them!
Transplanting: Bok choy transplants do better when you wait until nighttime temperatures are consistently maintained above 50 degrees F. If you move them outdoors in cooler temperatures, be sure to cover them. When exposed to frost or prolonged cold temperatures, bok choy plants may mistake it for winter and start to bolt as soon as the weather warms up.
Water: When planting bok choy, be sure to water your starter soil and garden bed well both before planting the seeds and immediately after. During the growing season, bok choy requires consistent watering, especially in the fall. Dry conditions will result in less juicy ribs and may also cause premature bolting.