When to plant green onion
Vegetable, hardy
Plant with bulb onions, 2–4 weeks before the last frost, and pull them young. Clemson lists 35–45 days from sets and CSU about 60 days from seed. The same 35°F versus 60°F soil-temperature disagreement applies as for bulb onions.
The general rule
- Sow outdoors
- 2–4 weeks before the last spring frost
- Plant when soil reaches
- 60°F
- Days to maturity
- 35–60 days
What that means in different climates
The same rule applied to the safer frost dates of cities from cold to frost-free.
| City | Last frost · safer | Sow outdoors |
|---|---|---|
| San Jose, CA | Jan 23 | Dec 26 – Jan 9 |
| Tucson, AZ | Mar 2 | Feb 2 – Feb 16 |
| Portland, OR | Mar 21 | Feb 21 – Mar 7 |
| Baltimore, MD | Apr 4 | Mar 7 – Mar 21 |
| New York, NY | Apr 12 | Mar 15 – Mar 29 |
| Nashville, TN | Apr 16 | Mar 19 – Apr 2 |
| Louisville, KY | Apr 23 | Mar 26 – Apr 9 |
| Omaha, NE | May 6 | Apr 8 – Apr 22 |
| Colorado Springs, CO | May 15 | Apr 17 – May 1 |
| Miami, FL | Frost rare | Frost is rare: fall and winter (soil 60°F+). |