How to grow Bok Choy

Where to plant

Bok choy grows best in mild weather, around 64 to 68°F (18 to 20°C), and tolerates a light frost. It bolts easily: long warm days, heat waves and spells of more than a week of nights below about 50°F (10°C) all push it to flower. Grow it in full sun in fertile, moisture holding but well drained soil, with a little afternoon shade if a warm spell arrives.

In Florida, the Gulf South, Texas, the desert and Southern California, sow from fall through winter, which UF/IFAS notes suits bok choy well. In the Mid-South and Mid-Atlantic, sow in early spring and again from mid August; midsummer heat stops germination. Across the North, the Midwest, the Mountain West and Alaska, sow in spring and again in midsummer for a fall crop, which is less likely to bolt.

Choosing a variety

Joi Choi is a white stemmed variety that is slow to bolt, ready in about 50 days. Toy Choi is a quick, compact type at about 45 days, and Mei Qing Choi is a baby type with small green stalks, ready in about 42 days. For spring sowings, choose varieties described as slow to bolt.

How to plant

1. Work compost into the bed before sowing and keep the prepared soil moist.
2. Sow seed about a quarter to half an inch (6 to 12 mm) deep, directly in the bed or, for spring crops, in individual cells or pots, since seedlings resent root disturbance.
3. Thin or plant out to about 8 inches (20 cm) apart in rows 12 inches (30 cm) apart. Use the thinnings as baby greens.
4. Transplant at four to five weeks old, before seedlings get too big, and keep them watered, as any check in growth can set off bolting.
5. Sow small batches every two to three weeks through the right season for a steady supply.

Watering and feeding

Keep the soil evenly moist from sowing to harvest. Drought stress toughens the stalks and is one of the quickest triggers for bolting. Mulch around the plants to hold moisture and keep the leaves clean.

Bok choy grows fast and likes fertile soil. Dig in compost before sowing; UF/IFAS suggests feeding it as you would broccoli or cabbage, and a light side dressing of nitrogen a few weeks after planting keeps growth quick and tender.

Pruning and care through the year

• Cover new sowings with insect netting or row cover to keep out flea beetles and cabbage butterflies.
• Pull plants that start to send up a flower stalk and eat them straight away, before the leaves turn bitter.
• Rotate with other cabbage family crops to reduce clubroot and black rot.

Harvesting

Cut whole plants at the base when they reach full size, usually 40 to 50 days after sowing, or cut individual outer leaves as needed. Baby types can be harvested at 4 to 6 inches (10 to 15 cm). Harvest promptly once plants are ready, before they bolt.

Freshly picked bok choy keeps only a day or two at room temperature, but five days or more in the fridge.

Growing in pots

Bok choy grows well in a pot or trough at least 10 inches (25 cm) deep with a rich potting mix. Baby types such as Toy Choi suit containers best. Keep the mix evenly moist, as pots dry quickly and the plants bolt when stressed.