Calais, ME frost dates
Last spring frostApr 21median date
First fall frostOct 26median date
Growing season188 daysfrost-free
Hardiness zone5bZone 5b
How Calais compares
- In 8 years out of 10, the last spring frost in Calais falls between April 9 and May 2, a 23-day window. The first fall frost falls between October 7 and November 9.
- The median last frost is 15 days earlier than the Maine median of May 6.
- Its 188-day growing season is among the longest of the 457 Maine places with a regular frost season.
- The last frost is 10 days earlier than the zone 5b median of May 1. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5b chart.
- The weather station records an average of 166 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 9 |
| 50% (median) | April 21 |
| 10% (safe for tender plants) | May 2 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 7 |
| 50% (median) | October 26 |
| 90% (late) | November 9 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Calais, ME
Calais, ME frost dates — last frost Apr 21, first frost Oct 26, zone 5b. whenisthelastfrost.com
Crop
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Start indoors: Jan 27 to Feb 10Transplant outside: Mar 24 to Apr 7
Start indoors: Feb 10 to Feb 24Transplant outside: May 5 to May 19
Start indoors: Feb 10 to Feb 24Transplant outside: May 5 to May 19
Start indoors: Feb 24 to Mar 10Transplant outside: Apr 28 to May 12
Start indoors: Feb 24 to Mar 10Transplant outside: Mar 31 to Apr 14Sow outdoors: Mar 24 to Apr 28Plant for fall: Aug 31 to Sep 28
Start indoors: Feb 24 to Mar 10Transplant outside: Mar 24 to Apr 7Sow outdoors: Mar 24 to Apr 7Plant for fall: Aug 17 to Sep 7
Start indoors: Feb 24 to Mar 10Transplant outside: Apr 7 to Apr 21Plant for fall: Jul 20 to Aug 10
Start indoors: Feb 24 to Mar 10Transplant outside: Mar 31 to Apr 14Plant for fall: Jul 20 to Aug 10
Start indoors: Feb 24 to Mar 10Transplant outside: Apr 7 to Apr 21Plant for fall: Jul 20 to Aug 10
Start indoors: Mar 10 to Mar 24Transplant outside: May 12 to May 26Sow outdoors: May 12 to May 26
Start indoors: Mar 10 to Mar 24Transplant outside: Apr 28 to May 12
Sow outdoors: Mar 10 to Mar 31Plant for fall: Aug 3 to Aug 24
Sow outdoors: Mar 10 to Mar 31Plant for fall: Aug 31 to Sep 21
Sow outdoors: Mar 17 to Apr 28Plant for fall: Sep 14 to Oct 5
Start indoors: Mar 24 to Mar 31Transplant outside: May 5 to May 12Sow outdoors: Apr 28 to May 12Plant for fall: Aug 10 to Aug 24
Start indoors: Mar 24 to Mar 31Sow outdoors: Apr 28 to May 12Plant for fall: Aug 17 to Aug 31
Start indoors: Mar 24 to Mar 31Sow outdoors: Apr 28 to May 12
Start indoors: Mar 24 to Mar 31Transplant outside: May 5 to May 19
Sow outdoors: Mar 31 to Apr 28Plant for fall: Aug 3 to Aug 17
Sow outdoors: Mar 31 to Apr 28Plant for fall: Aug 17 to Aug 31
Sow outdoors: Mar 31 to Apr 21
Sow outdoors: Apr 7 to May 5Plant for fall: Aug 17 to Aug 31
Sow outdoors: Apr 7 to Apr 28Plant for fall: Aug 31 to Sep 21
Sow outdoors: Apr 28 to May 19Plant for fall: Aug 10 to Aug 24
Sow outdoors: Apr 28 to May 12
Transplant outside: May 5 to May 26
Plant for fall: Oct 12 to Nov 16
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Calais, ME
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 27 – Feb 10 | Mar 24 – Apr 7 | — | — |
| Peppers | Feb 10 – Feb 24 | May 5 – May 19 | — | — |
| Eggplant | Feb 10 – Feb 24 | May 5 – May 19 | — | — |
| Tomatoes | Feb 24 – Mar 10 | Apr 28 – May 12 | — | — |
| Lettuce | Feb 24 – Mar 10 | Mar 31 – Apr 14 | Mar 24 – Apr 28 | Aug 31 – Sep 28 |
| Kale | Feb 24 – Mar 10 | Mar 24 – Apr 7 | Mar 24 – Apr 7 | Aug 17 – Sep 7 |
| Broccoli | Feb 24 – Mar 10 | Apr 7 – Apr 21 | — | Jul 20 – Aug 10 |
| Cabbage | Feb 24 – Mar 10 | Mar 31 – Apr 14 | — | Jul 20 – Aug 10 |
| Cauliflower | Feb 24 – Mar 10 | Apr 7 – Apr 21 | — | Jul 20 – Aug 10 |
| Okra | Mar 10 – Mar 24 | May 12 – May 26 | May 12 – May 26 | — |
| Basil | Mar 10 – Mar 24 | Apr 28 – May 12 | — | — |
| Peas | — | — | Mar 10 – Mar 31 | Aug 3 – Aug 24 |
| Spinach | — | — | Mar 10 – Mar 31 | Aug 31 – Sep 21 |
| Radishes | — | — | Mar 17 – Apr 28 | Sep 14 – Oct 5 |
| Cucumbers | Mar 24 – Mar 31 | May 5 – May 12 | Apr 28 – May 12 | Aug 10 – Aug 24 |
| Zucchini & Summer Squash | Mar 24 – Mar 31 | — | Apr 28 – May 12 | Aug 17 – Aug 31 |
| Winter Squash & Pumpkins | Mar 24 – Mar 31 | — | Apr 28 – May 12 | — |
| Melons & Watermelon | Mar 24 – Mar 31 | May 5 – May 19 | — | — |
| Carrots | — | — | Mar 31 – Apr 28 | Aug 3 – Aug 17 |
| Beets | — | — | Mar 31 – Apr 28 | Aug 17 – Aug 31 |
| Potatoes | — | — | Mar 31 – Apr 21 | — |
| Swiss Chard | — | — | Apr 7 – May 5 | Aug 17 – Aug 31 |
| Cilantro | — | — | Apr 7 – Apr 28 | Aug 31 – Sep 21 |
| Green Beans | — | — | Apr 28 – May 19 | Aug 10 – Aug 24 |
| Sweet Corn | — | — | Apr 28 – May 12 | — |
| Sweet Potatoes | — | May 5 – May 26 | — | — |
| Garlic | — | — | — | Oct 12 – Nov 16 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Woodland, ME weather station, 11 km away (elevation 125 ft (38 m)).
Frost dates near Calais
- Robbinston May 5 · Oct 13
- Baileyville Apr 21 · Oct 26
- Meddybemps Apr 21 · Oct 26
- Pembroke May 5 · Oct 13
- Perry May 5 · Oct 13
- Princeton May 4 · Oct 10
- Dennysville Apr 29 · Oct 25
- Eastport Apr 29 · Oct 25
- Lubec Apr 29 · Oct 25
- Waite May 6 · Oct 8
Frequently asked questions
When is the last frost in Calais, ME?
The median last spring frost in Calais, ME is April 21. There is still about a 10% chance of frost after May 2, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Calais, ME?
The median first fall frost is October 26, with about a 10% chance of frost before October 7.
How long is the growing season in Calais, ME?
About 188 days between the median last spring frost and first fall frost.
What planting zone is Calais, ME?
Calais, ME is in USDA hardiness zone 5b.