When to plant Onion sets in Delaware
In spring, from Feb 15 – Mar 20 in Dover to Mar 1 – Apr 1 in Wilmington.
USDA's earliest safe spring and latest safe fall planting dates, matched to each place's average frost dates.
| Place | Spring | Fall |
|---|---|---|
| Dover | Feb 15 – Mar 20 | Not listed |
| Middletown | Mar 1 – Apr 1 | Not listed |
| Milford | Mar 1 – Apr 1 | Not listed |
| Newark | Mar 1 – Apr 1 | Not listed |
| Smyrna | Feb 15 – Mar 20 | Not listed |
| Wilmington | Mar 1 – Apr 1 | Not listed |
Planting dates: USDA Home and Garden Bulletin No. 9 (1967), tables 4 and 5. Frost dates: NOAA U.S. Climate Normals 1991–2020. “—” means the place's frost date is outside the table. The full USDA table for onion sets.