When to plant radish in New Hampshire
New Hampshire spans USDA zones 5a–6a, so the right time to plant radish shifts by weeks across the state. The window to sow seed directly outdoors runs from about April 1 in Nashua to April 16 in Keene — below are local dates for 15 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Direct sow |
|---|---|---|---|---|
| Manchester | 6a | April 30 | October 11 | April 2 – May 14 |
| Nashua | 6a | April 29 | October 8 | April 1 – May 13 |
| Concord | 5b | May 8 | October 3 | April 10 – May 22 |
| Dover | 6a | May 3 | October 10 | April 5 – May 17 |
| Rochester | 6a | April 30 | October 9 | April 2 – May 14 |
| Keene | 5b | May 14 | October 1 | April 16 – May 28 |
| Portsmouth | 6a | May 4 | October 8 | April 6 – May 18 |
| Derry | 6a | April 30 | October 11 | April 2 – May 14 |
Radish in New Hampshire: FAQ
When can I plant radish in New Hampshire?
Across New Hampshire, the time to direct-sow radish spans roughly April 1 in Nashua to April 16 in Keene, each following that city's local frost dates.
Does the radish planting date vary across New Hampshire?
Yes. New Hampshire publishes 15 cities with their own frost dates, so the right radish 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 radish take to grow in New Hampshire?
Radish takes about 22–30 days to reach harvest once planted — check that this fits inside your city's frost-free season on its place page.
Never miss a window in your area
An email when it’s time to start seeds, transplant, and sow — timed to your frost dates. Double opt-in, one-click unsubscribe, no spam.