Bok Choy

Bok choy, also called pak choi, is a leafy vegetable in the mustard family that grows as a loose head of leaves on a pale stalk. It is a cool-season crop, and both the leaves and stems are edible raw or cooked. Plants are described as annuals to biennials.

Sow bok choy in spring or fall, either by sowing seeds directly in the garden or by setting out transplants. Bury seeds ¼ to ½ inch (0.6 to 1.3 cm) deep and thin plants to 6 inches (15 cm) apart. Grow them in fertile, moist, well-drained soil with a pH of 6.0 to 7.5, and get a soil test before planting. Because the plants tolerate light frost, early spring and late fall plantings can survive.

Bok choy is said to need about 8 hours a day of sun, which can be hard to get in winter. Supplemental light, such as a grow light in a greenhouse, may be needed. The plant grows slower in less light but can tolerate as little as 2 hours of sun a day.

Harden off seedlings outdoors before planting them in the soil. Some pak choi varieties do not germinate well, while other varieties do, so choose varieties carefully.

Watering. Keep seedlings moist, but don’t overwater them, and don’t let them dry out.

Containers. Bok choy can be grown in a container at least 1 gallon (3.8 L) in size, with a depth of 20 inches (51 cm).

Pests. Row covers can reduce insect damage.

Common pests include aphids, whiteflies, flea beetles, caterpillars such as cabbage loopers, cutworms and beet armyworms, plus slugs and snails. Diseases include club root, white rust, leaf spot, damping off and bacterial soft rot. Seedlings with thin stems that fall over may be affected by temperatures that are too warm or prolonged cold.

Plants mature in about 60 days. Harvest the largest, outermost leaves first for a steady supply, or cut the whole head at once. If the plant bolts, cut the head before the flowers open and use it as normal.

Bok choy keeps in the refrigerator for one to two weeks, but its quality drops quickly in storage.

Bok choy is listed as a problem for horses, with no part of the plant named. Leaves and stems are edible raw or cooked, and the flowers can be eaten too.