Green Onions in Zone 7B — Texas

Green onions are a must-grow for any Texas gardener. Their mild, fresh flavor elevates everything from tacos to salads, and they're incredibly versatile in the kitchen. Plus, there's nothing quite like the satisfaction of snipping fresh green onions from your own backyard, especially when you can harvest them twice a year!

Our unpredictable Texas weather, with its potential for both drought and flash floods, can be a challenge. But with a little planning, you can enjoy a continuous supply of green onions throughout our long, 255-day growing season. Timing is key, and we'll help you navigate it.

You can transplant green onion seedlings outdoors in early February through early March. This gives them a head start before the full force of the Texas heat arrives. Remember to harden off your seedlings for about a week before planting. Gradually expose them to outdoor conditions to prevent shock.

Space transplants about 2-3 inches apart in well-draining soil. Keep an eye on the forecast. Those early months can bring unexpected freezes, so be ready to cover your young plants if temperatures dip.

Direct sowing is the easiest way to grow green onions in Texas. You can sow seeds directly into the garden from early February through early September, giving you a long window for multiple plantings. Soil temperatures need to be at least 50°F for good germination.

Prepare your soil by loosening it and adding compost. Sow seeds about ¼ inch deep and 2-3 inches apart. Keep the soil consistently moist until the seedlings emerge. A little tip: you can also plant the root ends of store-bought green onions! Just stick them in the ground, and they'll regrow.

Green onions need consistent moisture to thrive, especially in the Texas heat. They aren't drought-tolerant, and their shallow roots can dry out quickly. A consistent water schedule is important because our rainfall is unpredictable.

In the spring and fall, aim for about 1 inch of water per week, either from rain or irrigation. During the brutal Texas summer, you might need to increase that to 1.5-2 inches per week. Use the "finger test" – stick your finger into the soil about 2 inches deep. If it feels dry, it's time to water. Water at the base of the plants to avoid wetting the foliage, especially with our variable humidity. Overhead watering can encourage fungal diseases.

If the leaves start to yellow and droop, you're likely overwatering. If they look dry and wilted, you're underwatering. A layer of mulch can help retain moisture and regulate soil temperature, which is especially helpful during the hot months.

You can expect your first harvest of green onions about 60 days after planting, starting in mid-April and continuing through late November. Green onions are ready to harvest when they are about pencil-thick. Don't wait too long, or they can become tough.

You can either pull up the entire plant or cut the green stalks about an inch above the soil line. If you cut them, they will usually regrow, giving you multiple harvests. As our first frost approaches around mid- November, harvest any remaining green onions. They are cold-hardy, but a hard freeze can damage them.

Here are some common problems you might encounter growing green onions in Texas:

• Onion Maggots
• What it looks like: Wilting plants, yellowish leaves, and small white maggots feeding on the roots and bulb.
• What causes it: These pests thrive in moist soil.
• How to fix/prevent it: Use row covers to prevent the adult flies from laying eggs. Apply beneficial nematodes to the soil.
• Thrips
• What it looks like: Silver streaks on the leaves, distorted growth, and tiny, slender insects.
• What causes it: Thrips are attracted to stressed plants, especially during hot, dry periods.
• How to fix/prevent it: Provide adequate water and fertilize regularly. Insecticidal soap or neem oil can help control infestations.
• Downy Mildew
• What it looks like: Yellow patches on leaf tops with fuzzy gray-purple growth on undersides. Leaves brown and die from the bottom up.
• What causes it: Oomycete pathogen that spreads in cool, humid conditions via wind-carried spores.
• How to fix/prevent it: Remove affected leaves immediately. Improve air circulation. Water at the base, never overhead. Copper-based fungicides for prevention.
• Pink Root
• What it looks like: Pink or reddish roots, stunted growth, and yellowing leaves.
• What causes it: A soilborne fungus that thrives in warm, wet conditions.
• How to fix/prevent it: Improve soil drainage. Rotate crops to avoid planting onions in the same spot year after year. Solarize the soil during the hot summer months to kill the fungus.

Texas Specific Challenges: The hot-to-extreme heat and variable humidity of Texas can exacerbate many of these problems. Ensure good air circulation and avoid overhead watering to prevent fungal diseases. Monitor your plants regularly and act quickly at the first sign of trouble. Also, watch out for fire ants, they can disrupt the roots.

Companion planting can help your green onions thrive. Carrots are great companions because they deter onion flies, while green onions deter carrot root flies. Lettuce benefits from the shade provided by green onions during the Texas heat. Tomatoes and peppers also benefit because green onions can repel certain pests. Beets are good companions because they don't compete for the same nutrients.

Avoid planting green onions near beans or peas. They can inhibit the growth of these legumes.