Green Onions in Zone 7A — Mid-Atlantic

Green onions are a must-have for any Mid-Atlantic garden. Their mild, fresh flavor elevates everything from summer salads to grilled dishes, and they're incredibly versatile in the kitchen. Plus, the satisfaction of snipping fresh green onions from your garden is hard to beat, especially after a long, cold winter.

We know our humid summers and variable spring weather can present challenges, but green onions are surprisingly adaptable. With a 208-day growing season in our zone, you have plenty of time to get several harvests. Careful timing and attention to watering will set you up for success.

If you're starting your green onions indoors, aim to transplant them outdoors in early March through early April. This gives them a good start before our humid summers kick in.

Before transplanting, be sure to harden off your seedlings. This means gradually exposing them to outdoor conditions for about a week, increasing their time outside each day. Space them 2-3 inches apart in well-drained soil.

Keep an eye on the weather forecast in early spring. We can still get some late frosts, so be ready to cover your transplants if needed.

Direct sowing is the easiest way to grow green onions in the Mid-Atlantic. You can sow seeds directly into the garden from early March through mid August, ensuring a continuous harvest throughout the growing season.

Prepare your soil by loosening it and amending with compost. Green onion seeds germinate best when the soil temperature is consistently above 50°F. Sow seeds about ¼ inch deep, spacing them 2-3 inches apart. 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 overwatering can lead to problems in our humid climate. Aim to keep the soil consistently moist, but not soggy. The goal is tender, mild stalks.

During the cooler spring and fall months, you'll likely only need to water once or twice a week, especially with our reliable rainfall. In the heat of summer, you may need to water every other day, or even daily if it's particularly dry. Stick your finger about 2 inches into the soil to check moisture levels – if it feels dry, it's time to water. Aim for about 1 inch of water per week.

Water at the base of the plants to avoid wetting the foliage, which can encourage fungal diseases in our humid summers. Signs of underwatering include yellowing leaves and stunted growth. Overwatering can lead to root rot, indicated by wilting and mushy stems. A layer of mulch can help retain moisture and suppress weeds – straw or shredded leaves work well.

You can expect your first harvest of green onions about 60 days after planting, usually from early May through early November. They're ready to harvest when the stalks are about pencil-thick.

You can either pull up the entire plant or cut the stalks off about an inch above the soil line. If you cut them, they'll often regrow for multiple harvests. For a continuous supply, plant a new batch of seeds every few weeks.

As our first frost approaches in late October, harvest any remaining green onions. You can chop and freeze them for use throughout the winter.

Here are some common problems you might encounter with green onions in the Mid-Atlantic:

Onion Maggots

• What it looks like: Wilting or yellowing leaves, stunted growth, and small white maggots feeding on the roots.
• What causes it: Flies lay eggs at the base of the plants, and the larvae burrow into the bulbs.
• How to fix/prevent it: Use row covers to prevent flies from laying eggs. Apply beneficial nematodes to the soil.

Thrips

• What it looks like: Silvery or white streaks on the leaves, distorted growth, and tiny, slender insects.
• What causes it: Thrips feed on the plant sap, causing damage to the leaves.
• How to fix/prevent it: Insecticidal soap or neem oil can help control thrip populations. Encourage beneficial insects like ladybugs.

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 infects the roots, hindering water and nutrient uptake.
• How to fix/prevent it: Improve soil drainage. Rotate crops regularly. Plant resistant varieties if available.

Mid-Atlantic Specific Challenges: Our moderate-to-hot summers and humid conditions can create an ideal environment for fungal diseases like downy mildew. Good air circulation and careful watering practices are essential. Deer pressure can also be an issue, so consider fencing or using deer repellent.

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, especially during our humid summers. Tomatoes and peppers also benefit from the pest-repelling properties of green onions. Beets are also good companions, as they don't compete for the same nutrients.

Avoid planting green onions near beans or peas. These legumes can inhibit onion growth.