Green Onions in Zone 7A — Texas

Green onions are a must-grow in Texas. Their mild, fresh flavor adds a zing to everything from tacos to salads, and they're so easy to grow in our long growing season. Plus, there's nothing quite like snipping fresh green onions from your own garden.

Sure, gardening in Texas comes with its challenges, like the unpredictable weather and the brutal Texas heat. But with our 245-day growing season and a little planning, you can enjoy a continuous harvest of green onions.

You can transplant green onions outdoors from mid February through mid March here in Texas. Before you get them in the ground, make sure to harden them off. Give them about a week of gradual exposure to the outdoors, increasing the time each day.

Space your transplants about 2-3 inches apart. Keep an eye on the weather forecast around transplant time, as those late cold snaps can sometimes sneak up on you.

Direct sowing is the easiest way to grow green onions in Texas. You can sow seeds from mid February through early September, giving you plenty of time for multiple harvests. Green onions prefer soil temperatures between 60°F and 70°F, so make sure the soil has warmed up a bit before planting.

Prepare your soil by loosening it and adding some compost. Sow the seeds about ¼ inch deep, spacing them 2-3 inches apart. Keep the soil consistently moist until they germinate. 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, but it's a delicate balance, especially with our variable humidity and unpredictable rainfall in Texas. They aren't drought tolerant, so don't let them dry out completely.

During the spring and fall, when the weather is milder, aim to water your green onions deeply once or twice a week. In the heat of the Texas summer, you might need to water them every day, especially if they're in full sun. Use the finger test: stick your finger about 2 inches into the soil. If it feels dry, it's time to water. Aim for about an inch of water per week, either from rainfall or irrigation.

Water at the base of the plants to avoid wetting the foliage, which can encourage fungal diseases in our humid conditions. Signs of underwatering include wilted or yellowing leaves, while overwatering can lead to root rot. A light layer of mulch, like shredded leaves or straw, can help retain moisture and keep the soil cool, which is especially helpful during the Texas heat.

You can expect your first harvest of green onions from mid April through late November in Texas, about 60 days after planting. They're ready to harvest when the stalks are about pencil-thick. You can either pull up the entire plant or cut the green tops off about an inch above the soil line.

If you cut them, they'll regrow, giving you a continuous harvest. To encourage continued production, make sure to keep them watered and fertilized. As the first frost approaches in mid- November, you can cover your green onions with a cold frame or row cover to extend the harvest a bit longer.

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

Onion Maggots

• What it looks like: Wilting or yellowing leaves, stunted growth, and small white maggots feeding on the roots and bulb.
• What causes it: These pests thrive in moist soil and can be attracted to the smell of onions.
• How to fix/prevent it: Use row covers to prevent the adult flies from laying eggs near your plants. Apply beneficial nematodes to the soil to kill the maggots.

Thrips

• What it looks like: Silver streaks or spots on the leaves, distorted growth, and tiny, slender insects.
• What causes it: Thrips are more prevalent during hot, dry weather.
• How to fix/prevent it: Encourage beneficial insects like ladybugs and lacewings. Use insecticidal soap or neem oil to 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: Roots turn pink or reddish, and the plant's growth is stunted.
• What causes it: A soilborne fungus that thrives in warm, moist conditions.
• How to fix/prevent it: Improve soil drainage. Rotate crops to avoid planting onions in the same spot year after year. Plant resistant varieties if available.

Texas Specific Challenges: The combination of hot-to-extreme heat, variable humidity, and unpredictable rainfall can create a challenging environment for green onions. The heat can stress the plants, making them more susceptible to pests and diseases. Flash floods can waterlog the soil, leading to root rot. It's important to monitor your plants closely and adjust your watering and pest control strategies as needed. Don't forget about fire ants, they can disturb the soil around the roots.

Good companions for green onions in Texas include carrots, lettuce, tomatoes, peppers, and beets. Carrots repel onion flies, while onions repel carrot flies. Lettuce provides ground cover, helping to retain moisture and suppress weeds. Tomatoes and peppers benefit from the onion's pest-repelling properties. Beets help to loosen the soil, making it easier for green onions to grow.

Avoid planting green onions near beans and peas. Onions can inhibit the growth of beans and peas, reducing their yields. This is especially important to consider in Texas, where we often plant beans and peas as part of our spring and fall gardens.