When to Plant Green Onions
Green onions are a hardy cool-season vegetable. They can take a hard frost.
Plant them out 1 to 4 weeks before the last spring frost. Or sow them where they will grow, 2 to 6 weeks before the last spring frost. For a fall crop, plant 4 to 8 weeks before the first fall frost. The first harvest comes about 55 to 70 days after sowing.
Example dates
The same rules in dates for three climates, using typical frost dates. Enter your ZIP code above for the dates where you live.
| Task | Last frost Mar 15first Nov 15 | Last frost Apr 15first Oct 25 | Last frost May 15first Sep 30 |
|---|---|---|---|
| Plant | Feb 15 – Mar 8 | Mar 18 – Apr 8 | Apr 17 – May 8 |
| Harvest | Apr 11 – May 9 | May 12 – Jun 9 | Jun 11 – Jul 9 |
| Direct-sown: Sow outdoors | Feb 1 – Mar 1 | Mar 4 – Apr 1 | Apr 3 – May 1 |
| Direct-sown: Harvest | Mar 28 – Apr 25 | Apr 28 – May 26 | May 28 – Jun 25 |
| Fall: Plant | Sep 20 – Oct 18 | Aug 30 – Sep 27 | Aug 5 – Sep 2 |
| Fall: Harvest | Nov 14 – Dec 12 | Oct 24 – Nov 21 | Sep 29 – Oct 27 |
Growing green onions
Plant thickly and pull as needed; sets give usable scallions a few weeks sooner than seed.
- Spacing: 1 in apart, in rows 12 in apart. In a raised bed, 16 per sq ft at square-foot spacing.
- Days to harvest: 55 to 70 from sowing, then about 4 weeks of picking.
- Successions: sow again every 21 days for a steady supply. See succession planting.
- Rotation: green onions are in the onion family. Plant them where nothing from that family grew in the last two years. See crop rotation.
- Traditional companions: beet, bell pepper, broccoli, brussels sprouts, cabbage, carrot, cauliflower, celery, chamomile (german), cherry tomato, collards, dill, head lettuce, hot pepper, kale, kohlrabi, leaf lettuce, romaine lettuce, salad mix (baby greens), spinach, strawberry, swiss chard, tomato. See companion plants for green onions.
- Usually kept apart from: bush bean, pea (shelling/snap/snow), pole bean.
Plan your beds with these dates
Draw your beds, tap squares to plant green onions and everything else, and get every crop's dates for your ZIP code in one calendar. Free, in your browser.
Open the garden plannerQuestions
Can green onions go in before the last frost?
Yes. Green onions are hardy: plant them out 1 to 4 weeks before the last spring frost.
How long do green onions take to grow?
About 55 to 70 days from sowing to the first harvest, which then lasts about 4 weeks. Varieties differ: check the seed packet.
Can I grow green onions in fall?
Yes. Set out transplants 4 to 8 weeks before the first fall frost. Enter your ZIP code above for the dates where you live.
How often should I sow green onions?
Every 21 days or so for a steady harvest, until the last sowing that still ripens before your first fall frost. The planner works that date out for your ZIP code.
More planting dates
Sources
- NOAA National Centers for Environmental Information, U.S. Climate Normals 1991–2020 (annual/seasonal, by station: freeze dates at 32 °F)
- Colorado State University Extension: Vegetable Planting Guide (CMG GardenNotes #720)
- NC State Extension: Extension Gardener Handbook, Chapter 16: Vegetable Gardening
- Iowa State University Extension and Outreach: Vegetable Planting and Harvesting Times (chart, central Iowa)
- Iowa State: Fall Planting of Vegetables
- Iowa State: Early Spring Planting of Vegetables
- Iowa State: All About Onions
- Clemson Cooperative Extension HGIC: Small-Scale Gardening (square-foot planting guide)
- UC Master Gardener Program, UC ANR: Companion Planting Chart: Companion Planting for Edible Crops
- University of Wisconsin–Madison Extension, Kenosha County: Companion Plants for the Vegetable Garden (column, 2012)
- Oregon State University Extension Service: Herbs and Flowers in the Vegetable Garden
- Utah State University Extension, Utah 4-H: Creating Sustainable School and Home Gardens: Companion Planting (2025)
- SDSU Extension: Square-Foot Garden Sample Planting Layout (P-00379, 2026)
- University of Arizona Cooperative Extension, Yavapai County: The Art of Companion Planting (Master Gardener presentation, 2023)
- Clemson Cooperative Extension HGIC: Plant Partners: 5 Benefits of Companion Planting (2025)
- N.C. A&T State University Cooperative Extension: Five Veggies You Can Grow at Home