Bok Choy in Zone 7A — Southeast

Bok choy is a fantastic addition to any Southeast garden. Its mild, slightly sweet flavor makes it incredibly versatile in stir-fries, soups, and salads. Plus, it's ready to harvest quickly, giving you a satisfyingly fast turnaround from seed to table, even in our long summer.

While our hot and humid summers can be a challenge for many cool-season crops, bok choy's relatively short maturity time and the ability to grow it in both spring and fall means you can easily enjoy it during our 225-day growing season. Careful timing and a few simple strategies will help you overcome potential issues.

Starting bok choy indoors is an option, especially if you want to get a jump start on the spring season. Sow seeds indoors from mid-February through mid-March, about four weeks before you plan to transplant. Use seed trays filled with a good seed-starting mix and provide consistent warmth and bright light, either from a sunny window or grow lights.

Bottom watering is a great way to keep the soil moist without overwatering, which is especially important in our moderately humid Southeast spring. Simply place the tray in a shallow dish of water and let the soil absorb the moisture from the bottom.

Transplant your bok choy seedlings outdoors from late March through early May, after they've developed a few sets of true leaves. Before transplanting, be sure to harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the sunlight, wind, and temperature fluctuations.

Space plants 6-10 inches apart in well-drained soil. Keep an eye on the weather, as late frosts can still occur during this time. If a frost is predicted, cover your seedlings with row covers or blankets to protect them.

Direct sowing bok choy is a simple and effective method, especially for fall crops. Sow seeds directly into the garden from mid-March through early September.

Prepare the soil by loosening it and adding compost or other organic matter. Bok choy seeds germinate best when the soil temperature is between 50°F and 70°F. Sow seeds about ¼ inch deep and space them 6-10 inches apart. Thin seedlings as needed once they emerge. Direct sowing is simple, but you'll need to stay on top of watering and weed control, especially with those spring afternoon thunderstorms.

Bok choy needs consistent moisture to thrive, especially in our hot and humid Southeast summers. Aim to keep the soil evenly moist, but not waterlogged. The finger test is your friend: stick your finger into the soil about two inches deep. If it feels dry, it's time to water.

During the spring and fall, when temperatures are milder and rainfall is more frequent, you may only need to water once or twice a week, providing about 1 inch of water each time. However, during the heat of summer, you might need to water more frequently, especially if you're not getting regular afternoon thunderstorms.

Water at the base of the plants to avoid wetting the leaves, which can increase the risk of fungal diseases in our humid climate. Signs of underwatering include wilting leaves and slow growth. Overwatering can lead to root rot, so watch out for yellowing leaves and a mushy stem base. Mulching around your bok choy plants with straw or wood chips helps retain moisture, suppress weeds, and keep the soil cool.

You can expect your first harvest of bok choy from late April through mid-November, depending on when you planted. Baby bok choy can be harvested when it reaches 6-8 inches tall, while full-size bok choy is ready when it's 12-15 inches tall.

To harvest, cut the plant above the base, leaving the roots intact. This allows the plant to regrow and produce more leaves for a continuous harvest. Keep an eye on the weather as the first frost approaches in early November. You can extend the harvest by covering the plants with row covers or bringing them indoors if a hard freeze is predicted.

Here are some common problems you might encounter growing bok choy in the Southeast:

Flea Beetles

• What it looks like: Tiny round holes (shot-hole pattern) in leaves. You'll see small dark beetles that jump when disturbed. The worst damage happens to young seedlings.
• What causes it: These small jumping beetles feed on the leaves, especially on young plants. They love our warm spring weather.
• How to fix/prevent it: Use row covers to protect seedlings. You can also delay planting until plants are larger and more resilient. Spray with kaolin clay or neem oil. Interplant with basil or catnip.

Cabbage Worms

• What it looks like: Smooth green caterpillars on the leaves, with irregular holes chewed in them. You might see dark green droppings and white butterflies flying around your plants.
• What causes it: These are the larvae of cabbage butterflies. We get multiple generations per season because of our long growing season.
• How to fix/prevent it: Bt spray is very effective. Floating row covers will prevent the butterflies from laying eggs. Handpick the caterpillars and interplant with aromatic herbs like thyme or sage to deter them.

Slugs

• What it looks like: Irregular holes in leaves, especially on low-growing plants. You'll see silvery slime trails on the leaves and soil. Damage is worse at night and in wet weather.
• What causes it: Slugs feed at night in moist conditions. They hide under mulch and debris during the day, which we have plenty of in our humid Southeast gardens.
• How to fix/prevent it: Use beer traps (shallow dishes of beer sunk into the soil). Iron phosphate bait is pet-safe. Remove hiding spots and water in the morning so the soil surface dries by evening. Copper tape around beds and diatomaceous earth around plants can also help.

Bolting in Heat

• What it looks like: The plant sends up a flower stalk, and the leaves become tough and bitter. Harvest quality declines rapidly.
• What causes it: Extended warm temperatures cause bolting. Bok choy bolts when days consistently exceed 80°F. This can be a challenge in our long, hot summers.
• How to fix/prevent it: Time your plantings for the cooler parts of the season (spring and fall). Choose bolt-resistant varieties. Provide shade during warm spells with shade cloth. Mulch to keep the soil cool and harvest before bolting progresses too far.

Southeast Specific Challenges: The combination of heat and humidity in the Southeast creates a perfect environment for fungal diseases to thrive on bok choy. Wet-summer rainfall patterns also increase the risk of slug and snail damage. Be vigilant about monitoring your plants and taking preventative measures to minimize these issues.

Good companions for bok choy include garlic and onions, which deter pests like aphids and cabbage moths. Beets are also a good choice, as they don't compete for the same nutrients and can help break up the clay soil common in our region. Lettuce and spinach are also beneficial, as they provide ground cover and help keep the soil cool and moist.

Avoid planting bok choy near strawberries, as they can attract slugs. Also, don't plant it near tomatoes, as they can compete for resources and attract similar pests.