Bok Choy in Zone 6B — Mid-Atlantic

Bok Choy is a winner in the Mid-Atlantic garden. It's incredibly versatile in the kitchen, adding a mild, slightly sweet flavor to stir-fries, soups, and salads. Plus, the satisfaction of harvesting your own crisp, fresh greens twice a year, in both spring and fall, is hard to beat.

We know our humid summers and variable spring weather can be a challenge. But with a little attention to timing, you can easily enjoy a bountiful Bok Choy harvest. Our 198-day growing season gives you plenty of opportunity to get it right.

Starting Bok Choy indoors in the Mid-Atlantic is an option, but honestly, it's often not necessary unless you're aiming for a very early spring harvest. If you want a head start, sow seeds indoors from early to late March, about four weeks before you plan to transplant.

Use seed trays or small pots filled with a good seed-starting mix. Keep them warm and provide plenty of light, either from a sunny window or a grow light. Bottom watering helps keep the soil evenly moist without damping off issues. Given our moderate spring, direct sowing often works just as well.

Transplant your Bok Choy seedlings outdoors from early April through late May, after hardening them off for about a week. This gradual exposure to outdoor conditions helps them adjust to the sun and wind.

Space the plants 6-10 inches apart. Keep an eye on the weather forecast, as we can still get some unexpected cool snaps in April. Be ready to cover the seedlings if a late frost threatens.

Direct sowing Bok Choy is easy and effective in the Mid-Atlantic. Sow seeds from late March through late August for a continuous harvest.

Prepare the soil by loosening it and adding compost. Bok Choy prefers soil temperatures between 50°F and 70°F for germination. Sow seeds about ¼ inch deep and 6-10 inches apart. Thin seedlings as needed once they emerge.

Bok Choy needs consistent moisture to thrive, especially during our humid summers. Aim for about 1 inch of water per week, either from rainfall or irrigation.

Stick your finger about 2 inches into the soil. If it feels dry, it's time to water. In the spring and fall, when temperatures are cooler, you may only need to water once or twice a week. During the heat of summer, you might need to water daily, especially if it hasn't rained. Water at the base of the plant to avoid wetting the leaves, which can encourage fungal diseases in our humid climate.

Underwatering can cause the leaves to wilt and the plant to bolt prematurely. Overwatering can lead to root rot. Yellowing leaves are a sign of overwatering. A layer of mulch, like straw or shredded leaves, helps retain moisture and keep the soil cool, which is especially helpful during our moderate-to-hot summers.

You can expect your first Bok Choy harvest from mid-May through early November, depending on when you planted. Bok Choy is ready to harvest about 45 days after sowing.

Harvest baby Bok Choy when it's 6-8 inches tall, or wait for full size at 12-15 inches. Cut the plant above the base, leaving the roots intact. This allows the plant to regrow for a second harvest.

For continuous production, harvest outer leaves as needed. As late October approaches and our first frost looms, harvest any remaining mature heads to enjoy before the cold weather sets in.

Here are a few common problems you might encounter with Bok Choy in the Mid-Atlantic:

Flea Beetles

• What it looks like: Tiny round holes (shot-hole pattern) in leaves, especially on young seedlings. You might see small, dark beetles that jump when disturbed.
• What causes it: Small jumping beetles that feed on leaves. They love young plants.
• How to fix/prevent it: Row covers are your best friend for protecting seedlings. You can also delay planting until the plants are larger. Kaolin clay or neem oil spray can help. Companion planting with basil or catnip might deter them, too.

Cabbage Worms

• What it looks like: Smooth green caterpillars chewing irregular holes in the leaves. You'll see dark green droppings and maybe even white butterflies fluttering around.
• What causes it: The larvae of those white cabbage butterflies. They can have multiple generations throughout our warm season.
• How to fix/prevent it: Bt spray is very effective. Floating row covers will prevent the butterflies from laying eggs. Handpicking the caterpillars works, too. Interplant with thyme or sage to confuse them.

Slugs

• What it looks like: Irregular holes in leaves, especially on plants close to the ground. Look for silvery slime trails, especially after a rainy night.
• What causes it: These gastropods feed at night in moist conditions. They hide under mulch and debris during the day. Our humid climate makes them happy.
• How to fix/prevent it: Beer traps (shallow dishes of beer sunk into the soil) work well. Iron phosphate bait is pet-safe. Remove any hiding spots. Water in the morning so the soil surface dries out 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. The leaves become tough and bitter, and the overall harvest quality declines.
• What causes it: Bok Choy is a cool-season crop, and it bolts when temperatures rise. This is common during our moderate-to-hot summers.
• How to fix/prevent it: Time your plantings for spring and fall. Choose bolt-resistant varieties. Provide shade during warm spells. Mulch to keep the soil cool. Harvest promptly before bolting progresses too far.

Mid-Atlantic Specific Challenges: Our humid summers can exacerbate pest and disease problems. Consistent moisture management is key to preventing bolting. Even rainfall helps, but supplemental watering might be needed in drier periods.

Good companions for Bok Choy in the Mid-Atlantic include garlic and onions. Their strong scent can deter pests like flea beetles and cabbage moths. Beets are also beneficial, as they don't compete for the same nutrients and can help improve soil structure. Lettuce and spinach make good ground cover, helping to suppress weeds and retain moisture.

Avoid planting Bok Choy near strawberries or tomatoes. Strawberries can attract slugs, which will then target your Bok Choy. Tomatoes can stunt the growth of brassicas.