Swiss Chard in Zone 8B — Texas

Swiss chard is a workhorse in the Texas garden. You can harvest it continually for months, and it stands up to our unpredictable weather better than some other greens. Plus, the colorful stems – red, yellow, even bright white – add a pop of beauty to your plate and your garden.

We all know gardening in Texas isn't always easy. The extreme heat, occasional drought, and unpredictable freezes can be tough on plants. But with a little planning and attention to timing, you can absolutely grow Swiss chard successfully during our long, 273-day growing season.

Starting Swiss chard indoors gives you a head start, especially for that early spring crop. Sow seeds indoors from late January through mid February, about four weeks before you plan to transplant. This is especially useful if we have a warm spell and you want to get a jump on the season.

Use seed trays or small pots filled with a good seed-starting mix. Keep the soil consistently moist, and provide warmth and plenty of light. Bottom watering is a great way to keep the soil evenly moist without disturbing the seeds.

Transplant your Swiss chard seedlings outdoors from late February through late March. Before transplanting, harden them off by gradually exposing them to outdoor conditions for about a week. This helps them adjust to the Texas sunshine and wind.

When transplanting, space the seedlings 8-12 inches apart in well-drained soil. Keep an eye on the weather forecast – a late freeze can still happen, so be prepared to cover your seedlings if necessary.

Direct sowing Swiss chard is another option, especially for a fall crop. You can direct sow from mid February through mid September. Just be aware that seeds may not germinate well in the peak of the summer's heat.

Prepare the soil by loosening it and removing any rocks or debris. Sow seeds about ½ inch deep, and keep the soil consistently moist until they germinate. Thin seedlings to 8-12 inches apart once they emerge.

Swiss chard needs consistent moisture, especially in the Texas heat. Water deeply and regularly, aiming for about 1 inch of water per week, depending on rainfall. During the hottest parts of the summer, you might need to water more frequently.

Stick your finger about 2 inches deep 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 when our humidity spikes.

Underwatering will cause the leaves to wilt and turn yellow. Overwatering can lead to root rot, especially in heavy clay soils. Mulching around your plants with straw or shredded leaves helps retain moisture and suppress weeds, which is a must in our climate.

You can expect your first harvest of Swiss chard from early April through early December, about 55 days after planting. Harvest the outer stalks when they are 8-12 inches long. The colorful stems are perfectly edible, so don't discard them.

Cut the stalks at the base of the plant, leaving the inner leaves to continue growing. This encourages continued production throughout the season. As the first frost approaches in late November, harvest any remaining leaves to use in soups, stews, or stir-fries.

Here are a few common problems you might encounter with Swiss chard in Texas:

• Leaf Miners
• What it looks like: Squiggly, pale tunnels inside the leaves.
• What causes it: Tiny flies lay eggs on the leaves, and the larvae burrow inside to feed. They thrive in warm weather.
• How to fix/prevent it: Cover plants with row covers to prevent the flies from laying eggs. Remove and destroy infested leaves.
• Aphids
• What it looks like: Clusters of tiny soft-bodied insects (green, black, or white) on stems and leaf undersides. Sticky honeydew residue. Curled or distorted new growth.
• What causes it: Rapid-reproducing sap-sucking insects. Populations explode in warm weather. Ant colonies may farm them for honeydew.
• How to fix/prevent it: Strong water spray knocks them off. Encourage ladybugs and lacewings (natural predators). Insecticidal soap for heavy infestations. Neem oil works systemically. Avoid excess nitrogen fertilizer (it attracts them).
• Cercospora Leaf Spot
• What it looks like: Small, circular spots on the leaves that start out brown and eventually turn gray.
• What causes it: A fungal disease that thrives in humid conditions.
• How to fix/prevent it: Space plants properly to allow for good air circulation. Avoid overhead watering. Remove and destroy infected leaves. Fungicides can be used in severe cases.
• Slugs
• What it looks like: Irregular holes in leaves, especially low-growing plants. Silvery slime trails on leaves and soil. Damage worse at night and in wet weather.
• What causes it: Gastropods that feed at night in moist conditions. Hide under mulch, boards, and debris during the day.
• How to fix/prevent it: Beer traps (shallow dish of beer sunk into soil). Iron phosphate bait (pet-safe). Remove hiding spots. Water in morning so soil surface dries by evening. Copper tape around beds. Diatomaceous earth around plants.

Texas Specific Challenges: The combination of hot-to-extreme heat, variable humidity, and unpredictable rainfall in Texas can create ideal conditions for pests and diseases to thrive. Monitor your plants regularly and take action quickly to prevent problems from getting out of hand. Remember that drought stress can also weaken plants, making them more susceptible to pests and diseases.

Good companions for Swiss chard include lettuce, onion, garlic, and green beans. Lettuce provides ground cover, helping to retain moisture and suppress weeds. Onions and garlic deter pests. Green beans fix nitrogen in the soil, which benefits the Swiss chard. Cabbage is another good companion because it can help deter certain pests that might otherwise target your chard.

Avoid planting Swiss chard near corn or potatoes. Corn can compete for nutrients, and potatoes are susceptible to similar diseases. These combinations can create problems in the Texas garden.