When to plant onion in District of Columbia
District of Columbia spans USDA zone 8a, so the right time to plant onion shifts by weeks across the state. The window to transplant seedlings outdoors runs from about March 1 in Washington to March 1 in Washington — below are local dates for 1 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Transplant out |
|---|---|---|---|---|
| Washington | 8a | March 29 | November 8 | March 1 – March 15 |
Onion in District of Columbia: FAQ
When can I plant onion in District of Columbia?
Across District of Columbia, the time to transplant onion spans roughly March 1 in Washington to March 1 in Washington, each following that city's local frost dates.
Does the onion planting date vary across District of Columbia?
Yes. District of Columbia publishes 1 cities with their own frost dates, so the right onion planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.
How long does onion take to grow in District of Columbia?
Onion takes about 90–110 days to reach harvest once planted — check that this fits inside your city's frost-free season on its place page.
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