Quick planting window
| Start indoors | January to February |
|---|---|
| Transplant | March to April |
| Sow seeds | March to April |
| Estimated harvest | June to July |
| Risk | Medium risk |
Month calendar
Scan the year by month to see seed starting, sowing, transplanting, and harvest timing.
Onion is a reasonable spring choice for North Carolina if you adjust for your local microclimate.
Next: ZIP code personalization
This is a state-level planning window based on typical frost timing and crop rules. Use local Extension guidance or a ZIP code frost-date tool before planting.
Planning notes
Days to maturity
110
Covered states
North Carolina
Frost window
March to April / October to November
Mountain, Piedmont, and coastal calendars need different timing.
Onion growing notes
The calendar window is only the first step. These growing details affect survival, plant vigor, and harvest quality.
Sun
Full sun.
Soil
Loose, fertile soil with good drainage.
Spacing
4-6 inches for bulbs.
Container
Use wide containers at least 8-10 inches deep.
Watering
Keep evenly moist during bulb formation.
Common mistake
Choosing the wrong day-length onion type.
Beginner tip
Use sets or transplants if seed timing feels too long.
Month window table
| Crop | Spring transplant / sow | Spring harvest | Fall transplant / sow | Fall harvest |
|---|---|---|---|---|
| Onion | March to April | June to July | July to August | November to December |
Sources and limits
This page uses North Carolina state-level frost windows, USDA zone ranges, and crop rules for planning. It does not replace local Extension or county-level guidance.
FAQ
When should I start onion seeds indoors in North Carolina?
For spring, the indoor seed-starting window is about January to February. Move later if your local frost date is later than the state average.
When should I transplant onion in North Carolina?
For spring, the transplant window is about March to April. Harden seedlings off before planting outside.
Can I sow onion outdoors in North Carolina?
Yes. The spring outdoor sowing window is about March to April, assuming soil and night temperatures are suitable.
When can I harvest onion in North Carolina?
Spring planting estimates a harvest around June to July; fall planting estimates about November to December. Variety and weather can shift this by several weeks.
Is onion risky in North Carolina?
Onion is a reasonable spring choice for North Carolina if you adjust for your local microclimate. For fall: Onion is a reasonable fall choice for North Carolina if you adjust for your local microclimate.
Do local differences inside North Carolina matter?
Mountain, Piedmont, and coastal calendars need different timing. Treat this as a state-level starter window and confirm with a local Extension or frost-date tool before planting.
What growing details matter most for onion?
Full sun. Loose, fertile soil with good drainage. Common mistake: Choosing the wrong day-length onion type.
Is this ZIP-code accurate?
No. This page uses state-level windows; ZIP-code frost dates, USDA zone matching, and reminder calendars are planned for the next phase.