When to plant yardlong bean in Maine
Maine spans USDA zones 5a–6a, so the right time to plant yardlong bean shifts by weeks across the state. The window to transplant seedlings outdoors runs from about May 9 in Lewiston to May 30 in Sanford — below are local dates for 13 cities, each computed from its own frost dates.
| City | Zone | Last frost | First frost | Transplant out |
|---|---|---|---|---|
| Portland | 6a | April 26 | October 15 | May 10 – May 17 |
| Lewiston | 5b | April 25 | October 19 | May 9 – May 16 |
| Bangor | 5a | May 4 | October 4 | May 18 – May 25 |
| South Portland | 6a | April 26 | October 15 | May 10 – May 17 |
| Auburn | 5b | April 25 | October 19 | May 9 – May 16 |
| Biddeford | 6a | May 9 | October 3 | May 23 – May 30 |
| Sanford | 5b | May 16 | September 30 | May 30 – June 6 |
| Saco | 6a | April 26 | October 15 | May 10 – May 17 |
Yardlong Bean in Maine: FAQ
When can I plant yardlong bean in Maine?
Across Maine, the time to transplant yardlong bean spans roughly May 9 in Lewiston to May 30 in Sanford, each following that city's local frost dates.
Does the yardlong bean planting date vary across Maine?
Yes. Maine publishes 13 cities with their own frost dates, so the right yardlong bean 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 yardlong bean take to grow in Maine?
Yardlong Bean takes about 70–90 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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