When to plant rhubarb in New Hampshire
New Hampshire spans USDA zones 5a–6a, so the right time to plant rhubarb shifts by weeks across the state. The window to transplant seedlings outdoors runs from about March 18 in Nashua to April 2 in Keene — below are local dates for 15 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Transplant out |
|---|---|---|---|---|
| Manchester | 6a | April 30 | October 11 | March 19 – April 16 |
| Nashua | 6a | April 29 | October 8 | March 18 – April 15 |
| Concord | 5b | May 8 | October 3 | March 27 – April 24 |
| Dover | 6a | May 3 | October 10 | March 22 – April 19 |
| Rochester | 6a | April 30 | October 9 | March 19 – April 16 |
| Keene | 5b | May 14 | October 1 | April 2 – April 30 |
| Portsmouth | 6a | May 4 | October 8 | March 23 – April 20 |
| Derry | 6a | April 30 | October 11 | March 19 – April 16 |
Rhubarb in New Hampshire: FAQ
When can I plant rhubarb in New Hampshire?
Across New Hampshire, the time to transplant rhubarb spans roughly March 18 in Nashua to April 2 in Keene, each following that city's local frost dates.
Does the rhubarb planting date vary across New Hampshire?
Yes. New Hampshire publishes 15 cities with their own frost dates, so the right rhubarb planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.
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