Frenchtown, MT frost dates
Last spring frostMay 18median date
First fall frostSep 25median date
Growing season130 daysfrost-free
Hardiness zone6aZone 6a
How Frenchtown compares
- In 8 years out of 10, the last spring frost in Frenchtown falls between May 5 and June 6, a 32-day window. The first fall frost falls between September 7 and October 6.
- The median last frost is 1 day earlier than the Montana median of May 19.
- Its 130-day growing season is longer than 60% of the 325 Montana places with a regular frost season (state median 125 days).
- The last frost is 19 days later than the zone 6a median of Apr 29. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6a chart.
- The weather station records an average of 183 nights a year at or below 32°F.
- Compared with Missoula, MT, 26 km away, the last frost here is 8 days later than there and the growing season is 14 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 5 |
| 50% (median) | May 18 |
| 10% (safe for tender plants) | June 6 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 7 |
| 50% (median) | September 25 |
| 90% (late) | October 6 |
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 Frenchtown, MT
Frenchtown, MT frost dates — last frost May 18, first frost Sep 25, zone 6a. whenisthelastfrost.com
Crop
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Start indoors: Feb 23 to Mar 9Transplant outside: Apr 20 to May 4
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 9 to Mar 23Transplant outside: Jun 1 to Jun 15
Start indoors: Mar 23 to Apr 6Transplant outside: May 25 to Jun 8
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Sow outdoors: Apr 20 to May 25Plant for fall: Jul 31 to Aug 28
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 20 to May 4Sow outdoors: Apr 20 to May 4Plant for fall: Jul 17 to Aug 7
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jun 19 to Jul 10
Start indoors: Mar 23 to Apr 6Transplant outside: Apr 27 to May 11Plant for fall: Jun 19 to Jul 10
Start indoors: Mar 23 to Apr 6Transplant outside: May 4 to May 18Plant for fall: Jun 19 to Jul 10
Start indoors: Apr 6 to Apr 20Transplant outside: Jun 8 to Jun 22Sow outdoors: Jun 8 to Jun 22
Start indoors: Apr 6 to Apr 20Transplant outside: May 25 to Jun 8
Sow outdoors: Apr 6 to Apr 27Plant for fall: Jul 3 to Jul 24
Sow outdoors: Apr 6 to Apr 27Plant for fall: Jul 31 to Aug 21
Sow outdoors: Apr 13 to May 25Plant for fall: Aug 14 to Sep 4
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 8Sow outdoors: May 25 to Jun 8Plant for fall: Jul 10 to Jul 24
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8Plant for fall: Jul 17 to Jul 31
Start indoors: Apr 20 to Apr 27Sow outdoors: May 25 to Jun 8
Start indoors: Apr 20 to Apr 27Transplant outside: Jun 1 to Jun 15
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 3 to Jul 17
Sow outdoors: Apr 27 to May 25Plant for fall: Jul 17 to Jul 31
Sow outdoors: Apr 27 to May 18
Sow outdoors: May 4 to Jun 1Plant for fall: Jul 17 to Jul 31
Sow outdoors: May 4 to May 25Plant for fall: Jul 31 to Aug 21
Sow outdoors: May 25 to Jun 15Plant for fall: Jul 10 to Jul 24
Sow outdoors: May 25 to Jun 8
Transplant outside: Jun 1 to Jun 22
Plant for fall: Sep 11 to Oct 16
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Frenchtown, MT
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 23 – Mar 9 | Apr 20 – May 4 | — | — |
| Peppers | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Eggplant | Mar 9 – Mar 23 | Jun 1 – Jun 15 | — | — |
| Tomatoes | Mar 23 – Apr 6 | May 25 – Jun 8 | — | — |
| Lettuce | Mar 23 – Apr 6 | Apr 27 – May 11 | Apr 20 – May 25 | Jul 31 – Aug 28 |
| Kale | Mar 23 – Apr 6 | Apr 20 – May 4 | Apr 20 – May 4 | Jul 17 – Aug 7 |
| Broccoli | Mar 23 – Apr 6 | May 4 – May 18 | — | Jun 19 – Jul 10 |
| Cabbage | Mar 23 – Apr 6 | Apr 27 – May 11 | — | Jun 19 – Jul 10 |
| Cauliflower | Mar 23 – Apr 6 | May 4 – May 18 | — | Jun 19 – Jul 10 |
| Okra | Apr 6 – Apr 20 | Jun 8 – Jun 22 | Jun 8 – Jun 22 | — |
| Basil | Apr 6 – Apr 20 | May 25 – Jun 8 | — | — |
| Peas | — | — | Apr 6 – Apr 27 | Jul 3 – Jul 24 |
| Spinach | — | — | Apr 6 – Apr 27 | Jul 31 – Aug 21 |
| Radishes | — | — | Apr 13 – May 25 | Aug 14 – Sep 4 |
| Cucumbers | Apr 20 – Apr 27 | Jun 1 – Jun 8 | May 25 – Jun 8 | Jul 10 – Jul 24 |
| Zucchini & Summer Squash | Apr 20 – Apr 27 | — | May 25 – Jun 8 | Jul 17 – Jul 31 |
| Winter Squash & Pumpkins | Apr 20 – Apr 27 | — | May 25 – Jun 8 | — |
| Melons & Watermelon | Apr 20 – Apr 27 | Jun 1 – Jun 15 | — | — |
| Carrots | — | — | Apr 27 – May 25 | Jul 3 – Jul 17 |
| Beets | — | — | Apr 27 – May 25 | Jul 17 – Jul 31 |
| Potatoes | — | — | Apr 27 – May 18 | — |
| Swiss Chard | — | — | May 4 – Jun 1 | Jul 17 – Jul 31 |
| Cilantro | — | — | May 4 – May 25 | Jul 31 – Aug 21 |
| Green Beans | — | — | May 25 – Jun 15 | Jul 10 – Jul 24 |
| Sweet Corn | — | — | May 25 – Jun 8 | — |
| Sweet Potatoes | — | Jun 1 – Jun 22 | — | — |
| Garlic | — | — | — | Sep 11 – Oct 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 Alberton, MT weather station, 17 km away (elevation 3,061 ft (933 m)).
Frost dates near Frenchtown
- Huson May 18 · Sep 25
- Alberton May 18 · Sep 25
- Arlee May 12 · Oct 2
- Missoula May 10 · Oct 1
- Ravalli May 12 · Oct 2
- Dixon May 12 · Oct 2
- Lolo May 16 · Sep 26
- Saint Ignatius May 12 · Oct 2
- Milltown May 10 · Oct 1
- Bonner May 10 · Oct 1
Frequently asked questions
When is the last frost in Frenchtown, MT?
The median last spring frost in Frenchtown, MT is May 18. There is still about a 10% chance of frost after June 6, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Frenchtown, MT?
The median first fall frost is September 25, with about a 10% chance of frost before September 7.
How long is the growing season in Frenchtown, MT?
About 130 days between the median last spring frost and first fall frost.
What planting zone is Frenchtown, MT?
Frenchtown, MT is in USDA hardiness zone 6a.