Bok Choy in Zone 9B — Texas

Bok choy is a fantastic addition to the Texas garden, offering crisp, mild flavor in stir-fries, soups, and salads. You'll appreciate how quickly it grows, giving you a satisfying harvest in just over a month, and how it thrives in our cooler seasons when the Texas heat backs off.

Our unpredictable weather and intense summer heat can be a challenge, but with careful timing, you can enjoy two successful harvests of Bok Choy during our long 308-day growing season. We'll focus on planting at the right times to avoid the worst of the heat.

Starting Bok Choy indoors makes sense if you want a head start on the spring season, especially with our early springs here in Texas. Start seeds indoors in early to late January, about four weeks before you plan to transplant.

Use seed trays or small pots filled with a good seed-starting mix. Keep them in a warm spot (around 70°F) and provide plenty of light – a grow light works wonders. Water from the bottom to keep the soil evenly moist without damping off.

Transplant your Bok Choy seedlings outdoors early February through mid March. Before transplanting, harden them off by gradually exposing them to outdoor conditions for about a week.

Space the seedlings 6-10 inches apart in well-draining soil. Keep an eye on the forecast – those unpredictable Texas freezes can still sneak in during this time, so be ready to cover your plants if needed.

Direct sowing Bok Choy is a great option, especially for the fall garden. You can direct sow late January through mid October, but remember that the best time to sow is when the soil is cool.

Prepare the soil by loosening it and adding compost. Sow seeds about ¼ inch deep and keep the soil consistently moist. Thin seedlings to 6-10 inches apart once they emerge. Direct sowing is convenient, but you'll need to be vigilant about pests, especially when the plants are young.

Bok Choy needs consistent moisture to thrive, especially in our variable Texas climate. Aim to keep the soil evenly moist, but not soggy.

During the spring and fall, when temperatures are milder, water deeply once or twice a week, providing about 1 inch of water. In the summer, you might need to water every day, especially if it's dry. Stick your finger about 2 inches into the soil – if it feels dry, it's time to water.

Water at the base of the plants to avoid wetting the leaves, which can encourage fungal diseases, particularly with our variable humidity. Signs of underwatering include wilting leaves, while yellowing leaves can indicate overwatering. Mulching around your Bok Choy plants with straw or shredded leaves can help retain moisture and regulate soil temperature, which is crucial in our unpredictable climate.

You can expect your first harvest of Bok Choy early March through mid December, about 45 days after planting. You can harvest baby Bok Choy when the leaves are 6-8 inches tall, or wait for the full-size heads to reach 12-15 inches.

To harvest, cut the entire head off at the base, or harvest individual outer leaves as needed. If you cut above the base, the plant may regrow for a second harvest.

As the first frost approaches in early December, harvest any remaining Bok Choy, even if it's small. It's better to harvest it before a freeze than to risk losing it.

Here are some common problems you might encounter growing Bok Choy in Texas:

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 is on young seedlings.
• What causes it: These small jumping beetles feed on the leaves, and they love brassicas. They're most damaging to small, young plants.
• How to fix/prevent it: Use row covers to protect seedlings during their vulnerable stage. You can also delay planting until plants are larger. Try a kaolin clay coating or neem oil spray. Interplant with basil or catnip. Healthy, vigorous plants often outgrow the damage.

Cabbage Worms

• What it looks like: Smooth green caterpillars on the leaves, with irregular holes chewed in them. You might also see dark green droppings and white butterflies hovering around your plants.
• What causes it: These are the larvae of white cabbage butterflies. We often have multiple generations per season in our warm climate.
• How to fix/prevent it: Bt spray is very effective. Floating row covers can prevent the butterflies from laying eggs. Handpick the caterpillars when you see them. Interplant with aromatic herbs like thyme and sage, and encourage parasitic wasps.

Slugs

• What it looks like: Irregular holes in the leaves, especially on low-growing plants. You'll see silvery slime trails on the leaves and soil. Damage is usually worse at night and in wet weather.
• What causes it: These gastropods feed at night in moist conditions. They hide under mulch, boards, and debris during the day.
• How to fix/prevent it: Try beer traps (shallow dishes of beer sunk into the soil). Iron phosphate bait is pet-safe. Remove any hiding spots. 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 when temperatures rise. The leaves become tough and bitter, and the harvest quality declines.
• What causes it: Extended warm temperatures above the plant's comfort zone. Bok Choy bolts when days consistently exceed 80°F.
• How to fix/prevent it: Time your plantings for the cooler weather of spring and fall. Choose bolt-resistant varieties. Provide shade during warm spells and mulch to keep the soil cool. Harvest before the bolting progresses too far.

Texas Specific Challenges: The extreme heat, variable humidity, and unpredictable rainfall in Texas mean you need to be extra vigilant about watering and providing shade for your Bok Choy. Bolting is a significant concern, so choose your planting times carefully to avoid the hottest parts of the year.

Good companions for Bok Choy include garlic and onions, as their strong scent can deter pests. Beets help to loosen the soil, which benefits Bok Choy's root growth. Lettuce and spinach, being low-growing, won't compete for sunlight and can even provide ground cover to help retain moisture.

Avoid planting Bok Choy near strawberries or tomatoes. Strawberries can attract slugs, which will also go after your Bok Choy. Tomatoes can stunt the growth of Bok Choy.