In USDA zone 7, the last spring frost usually falls between Apr 1 and Apr 20. Start onions indoors around Jan 20 to Feb 20. Plant them out around Apr 3 to Apr 28. Expect to harvest around Aug 3 to Sep 9.
| Start seeds indoors | Jan 20 to Feb 20 |
|---|---|
| Plant outside | Apr 3 to Apr 28 |
| Harvest | Aug 3 to Sep 9 |
| Typical last spring frost | Apr 1 to Apr 20 |
| Typical first fall frost | around Oct 15 |
USDA zones measure winter cold, not frost dates, so these are typical dates for the zone. Towns in the same zone can be weeks apart.
Get dates for onions in your exact town, not just your zone.
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