Mustard Greens in Zone 7B — Texas

Mustard greens are a fantastic addition to any Texas garden. Their peppery bite adds zest to salads, stir-fries, and soups. Plus, they're quick to mature, providing a harvest in both our spring and fall growing seasons, dodging the worst of the Texas heat.

Our unpredictable weather can be a challenge, but mustard greens are surprisingly resilient when timed right. With our long, 255-day growing season, you can easily squeeze in a spring and fall crop if you plan accordingly.

Starting mustard greens indoors is an option, especially for an early spring crop, but honestly, it's often not necessary in Texas. Our springs arrive early, and mustard greens germinate easily outdoors.

If you *do* want a head start, sow seeds indoors from late January through mid February, about three weeks before you plan to transplant. Use seed trays with a good seed-starting mix, provide warmth (a heat mat helps), and ensure they get plenty of light, either from a grow light or a very sunny window. Water from the bottom to avoid damping off. Since spring comes early here, you'll want to get started sooner than later.

Transplant your mustard green seedlings outdoors from late February through early April. Before transplanting, harden them off by gradually exposing them to outdoor conditions for about a week.

Space them 6-12 inches apart in well-drained soil. Keep an eye on the weather forecast – a late freeze can happen, so be prepared to cover your seedlings if temperatures dip unexpectedly.

Direct sowing is the easiest way to grow mustard greens in Texas. You can sow seeds directly into the garden from early February through late September for a continuous harvest.

Prepare the soil by loosening it and adding compost. Mustard greens prefer a soil temperature of at least 45°F for germination. Sow seeds about ½ inch deep and space them 6-12 inches apart, or sow them closer together and thin later. Direct sowing avoids transplant shock, but you'll need to be diligent about watering, especially during our hot summers.

Mustard greens need consistent moisture, especially in our variable Texas climate. While they can tolerate short periods of dryness, drought stress makes the leaves spicier and can trigger bolting, which ruins your harvest.

During the spring and fall, aim to water deeply once or twice a week, providing about 1 inch of water. In the heat of summer, you might need to water every other day or even daily, especially if rainfall is scarce. The "finger test" is your best guide: 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, especially with our variable humidity. Watch for signs of underwatering (wilting leaves) or overwatering (yellowing leaves). A layer of mulch, like shredded leaves or straw, will help retain moisture and keep the soil cool, which is crucial during the Texas heat.

You can expect your first harvest of mustard greens about 45 days after planting, which means from late March through late November. Harvest young leaves when they are about 4-6 inches long for a milder flavor. Larger leaves will be spicier.

To harvest, simply snip off the outer leaves, leaving the inner leaves to continue growing. This encourages continuous production. Be sure to harvest before the plant starts to flower (bolt), as the leaves will become bitter. As the first frost approaches in mid- November, harvest any remaining leaves or consider covering the plants to extend the harvest a bit longer.

Here are some common problems you might encounter growing mustard greens 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. Young seedlings suffer the most.
• What causes it: Small jumping beetles feeding on the leaves. They love brassicas.
• How to fix/prevent it: Use row covers to protect seedlings. Delay planting until plants are larger and more resilient. You can try a kaolin clay coating or neem oil spray. Interplanting with basil or catnip can also help deter them.

Aphids

• What it looks like: Clusters of tiny, soft-bodied insects (green, black, or white) on stems and leaf undersides. You might also see sticky honeydew residue and curled or distorted new growth.
• What causes it: Rapidly reproducing sap-sucking insects. Populations explode in warm weather, and ants often "farm" them.
• How to fix/prevent it: A strong spray of water will knock them off. Encourage ladybugs and lacewings. Insecticidal soap works well for heavy infestations, and neem oil can be used systemically. Avoid over-fertilizing with nitrogen.

Cabbage Worms

• What it looks like: Smooth green caterpillars on the leaves with irregular holes chewed in them. You'll see dark green droppings, and white butterflies fluttering around your plants.
• What causes it: Larvae of those white cabbage butterflies. They have multiple generations per season in our warm climate.
• How to fix/prevent it: Bt spray is very effective. Floating row covers will prevent the butterflies from laying eggs. Handpick the caterpillars when you see them. Interplant with aromatic herbs like thyme or sage.

Bolting in Heat

• What it looks like: The plant sends up a flower stalk, and the leaves become tough and bitter.
• What causes it: Extended warm temperatures (above 80°F) trigger bolting.
• How to fix/prevent it: Time your plantings for cooler weather in spring and fall. Choose bolt-resistant varieties. Provide shade during warm spells, and mulch to keep the soil cool. Harvest leaves before bolting progresses too far.

Texas Specific Challenges: Our hot-to-extreme heat, variable humidity, and unpredictable rainfall can stress mustard greens, making them more susceptible to pests and diseases. Consistent watering and careful timing of plantings are key to success. Also, watch out for fire ants when you're working in the garden!

Good companions for mustard greens include onions and garlic, which deter pests with their strong scent. Beets are also a good choice, as they don't compete for the same nutrients. Dill attracts beneficial insects that prey on aphids and other pests. Lettuce provides ground cover, helping to keep the soil cool and moist.

Avoid planting mustard greens near strawberries or tomatoes. Strawberries are susceptible to some of the same fungal diseases as mustard greens, and tomatoes may compete for the same nutrients.