🌱 When to Plant Scallions

Scallions, also called green onions or bunching onions, are one of the fastest and most forgiving crops in a kitchen garden. Unlike bulb onions, you harvest the whole young plant, so there’s no long wait for a mature bulb to fill out. Their cold tolerance also makes them one of the first crops you can put in the ground each spring.

Recommended Varieties

Most scallion seed sold in the U.S. is a bunching onion (Allium fistulosum), a true perennial that clumps and regrows instead of forming a bulb. White Lisbon is the classic all-purpose scallion, ready in about 60 days with straight white shafts. Evergreen Hardy White is bred for cold tolerance and often survives winter outdoors in zone 6 and warmer, resprouting the following spring. For color, Deep Purple or Red Beard produce scallions with a rosy blush partway up the stalk that holds up well in salads and garnishes.

If a seed packet is simply labeled “onion” rather than “bunching onion” or “scallion,” it’s a common onion (Allium cepa) meant to bulb. You can still harvest it young as a green onion, but it won’t regrow from the base the way true bunching types do.

Spacing, Sun & Soil

Scallions need less room than bulb onions since you’re not waiting for a bulb to swell. Sow seed about 1/2 inch deep and thin seedlings to 1-2 inches apart in rows spaced 6-12 inches apart. Because you’re harvesting the whole plant young, you can grow them closer together than most onions.

Give scallions full sun, at least 6 hours a day, though they’ll tolerate light afternoon shade in hot climates. They do best in loose, fertile soil with a pH between 6.0 and 7.0. Work an inch or two of compost into the bed before planting, since alliums are heavy feeders, and avoid heavy clay that stays wet, which encourages rot at the base.

Watering

Scallions have shallow roots and dry out fast, so keep the soil evenly moist rather than letting it swing between soggy and dry. About 1 inch of water a week is a reasonable starting point, more during hot, dry stretches. A layer of mulch around the base helps hold moisture and keeps weeds down, which matters since young scallions compete poorly with weeds.

Top Growing Tips

• Succession-sow every 2-3 weeks for a continuous supply through the season
• Harvest when tops are 6-8 inches tall and the base is pencil-thick
• Cut 1-2 inches above the soil line to regrow multiple harvests from the same planting
• Grow in containers on a porch or windowsill for a year-round indoor supply
• Interplant with carrots since scallions help repel carrot fly
• Direct sow where possible; scallions establish faster from seed sown in place than from transplants

Companion Planting

Good companions: carrots, tomatoes, peppers, beets, lettuce, and strawberries. Scallions’ strong scent helps mask the smell of carrots from carrot fly and can deter aphids from nearby plants.

Avoid planting near: beans and peas, since onions release compounds that inhibit the nitrogen-fixing bacteria legumes depend on. Asparagus is also a poor match; the two compete for similar root space without benefiting each other.

Common Problems

Onion thrips are the most frequent pest, showing up as silvery streaks on the leaves during hot, dry weather. A strong water spray or insecticidal soap knocks populations back. Onion maggot larvae tunnel into the base and are worse in cool, wet spring soil; crop rotation and floating row cover over young seedlings are the best defenses. In humid climates, watch for downy mildew, which appears as pale, fuzzy patches on the leaves. Thin plantings and water at the soil line rather than overhead to keep foliage dry. Scallions can also bolt if a cold snap hits young plants followed by a heat spike; bolted scallions are still edible, but the shafts turn woody at the core.

Harvest Timeline

Baby scallions can be pulled as early as 30-45 days, once the tops reach pencil thickness. Most varieties reach full size in 50-70 days from seed. Rather than pulling the whole plant, cut the tops 1-2 inches above the soil line and the base will regrow, often two or three more times before it’s spent. If you’re growing a true bunching variety like Evergreen Hardy White, leave a few clumps in the ground through fall. In zone 6 and warmer they’ll overwinter and resume growth the following spring, turning one planting into a perennial patch.