Rapelje, MT frost dates
Last spring frostMay 24median date
First fall frostSep 21median date
Growing season120 daysfrost-free
Hardiness zone4bZone 4b
How Rapelje compares
- In 8 years out of 10, the last spring frost in Rapelje falls between May 11 and June 11, a 31-day window. The first fall frost falls between September 4 and October 4.
- The median last frost is 5 days later than the Montana median of May 19.
- Its 120-day growing season is longer than 34% of the 325 Montana places with a regular frost season (state median 125 days).
- The last frost is 16 days later than the zone 4b median of May 8. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4b chart.
- The weather station records an average of 175 nights a year at or below 32°F.
- Compared with Billings, MT, 62 km away, the last frost here is 20 days later than there and the growing season is 36 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 11 |
| 50% (median) | May 24 |
| 10% (safe for tender plants) | June 11 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 4 |
| 50% (median) | September 21 |
| 90% (late) | October 4 |
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 Rapelje, MT
Rapelje, MT frost dates — last frost May 24, first frost Sep 21, zone 4b. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Mar 1 to Mar 15Transplant outside: Apr 26 to May 10
Start indoors: Mar 15 to Mar 29Transplant outside: Jun 7 to Jun 21
Start indoors: Mar 15 to Mar 29Transplant outside: Jun 7 to Jun 21
Start indoors: Mar 29 to Apr 12Transplant outside: May 31 to Jun 14
Start indoors: Mar 29 to Apr 12Transplant outside: May 3 to May 17Sow outdoors: Apr 26 to May 31Plant for fall: Jul 27 to Aug 24
Start indoors: Mar 29 to Apr 12Transplant outside: Apr 26 to May 10Sow outdoors: Apr 26 to May 10Plant for fall: Jul 13 to Aug 3
Start indoors: Mar 29 to Apr 12Transplant outside: May 10 to May 24Plant for fall: Jun 15 to Jul 6
Start indoors: Mar 29 to Apr 12Transplant outside: May 3 to May 17Plant for fall: Jun 15 to Jul 6
Start indoors: Mar 29 to Apr 12Transplant outside: May 10 to May 24Plant for fall: Jun 15 to Jul 6
Start indoors: Apr 12 to Apr 26Transplant outside: Jun 14 to Jun 28Sow outdoors: Jun 14 to Jun 28
Start indoors: Apr 12 to Apr 26Transplant outside: May 31 to Jun 14
Sow outdoors: Apr 12 to May 3Plant for fall: Jun 29 to Jul 20
Sow outdoors: Apr 12 to May 3Plant for fall: Jul 27 to Aug 17
Sow outdoors: Apr 19 to May 31Plant for fall: Aug 10 to Aug 31
Start indoors: Apr 26 to May 3Transplant outside: Jun 7 to Jun 14Sow outdoors: May 31 to Jun 14Plant for fall: Jul 6 to Jul 20
Start indoors: Apr 26 to May 3Sow outdoors: May 31 to Jun 14Plant for fall: Jul 13 to Jul 27
Start indoors: Apr 26 to May 3Sow outdoors: May 31 to Jun 14
Start indoors: Apr 26 to May 3Transplant outside: Jun 7 to Jun 21
Sow outdoors: May 3 to May 31Plant for fall: Jun 29 to Jul 13
Sow outdoors: May 3 to May 31Plant for fall: Jul 13 to Jul 27
Sow outdoors: May 3 to May 24
Sow outdoors: May 10 to Jun 7Plant for fall: Jul 13 to Jul 27
Sow outdoors: May 10 to May 31Plant for fall: Jul 27 to Aug 17
Sow outdoors: May 31 to Jun 21Plant for fall: Jul 6 to Jul 20
Sow outdoors: May 31 to Jun 14
Transplant outside: Jun 7 to Jun 28
Plant for fall: Sep 7 to Oct 12
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Rapelje, MT
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Mar 1 – Mar 15 | Apr 26 – May 10 | — | — |
| Peppers | Mar 15 – Mar 29 | Jun 7 – Jun 21 | — | — |
| Eggplant | Mar 15 – Mar 29 | Jun 7 – Jun 21 | — | — |
| Tomatoes | Mar 29 – Apr 12 | May 31 – Jun 14 | — | — |
| Lettuce | Mar 29 – Apr 12 | May 3 – May 17 | Apr 26 – May 31 | Jul 27 – Aug 24 |
| Kale | Mar 29 – Apr 12 | Apr 26 – May 10 | Apr 26 – May 10 | Jul 13 – Aug 3 |
| Broccoli | Mar 29 – Apr 12 | May 10 – May 24 | — | Jun 15 – Jul 6 |
| Cabbage | Mar 29 – Apr 12 | May 3 – May 17 | — | Jun 15 – Jul 6 |
| Cauliflower | Mar 29 – Apr 12 | May 10 – May 24 | — | Jun 15 – Jul 6 |
| Okra | Apr 12 – Apr 26 | Jun 14 – Jun 28 | Jun 14 – Jun 28 | — |
| Basil | Apr 12 – Apr 26 | May 31 – Jun 14 | — | — |
| Peas | — | — | Apr 12 – May 3 | Jun 29 – Jul 20 |
| Spinach | — | — | Apr 12 – May 3 | Jul 27 – Aug 17 |
| Radishes | — | — | Apr 19 – May 31 | Aug 10 – Aug 31 |
| Cucumbers | Apr 26 – May 3 | Jun 7 – Jun 14 | May 31 – Jun 14 | Jul 6 – Jul 20 |
| Zucchini & Summer Squash | Apr 26 – May 3 | — | May 31 – Jun 14 | Jul 13 – Jul 27 |
| Winter Squash & Pumpkins | Apr 26 – May 3 | — | May 31 – Jun 14 | — |
| Melons & Watermelon | Apr 26 – May 3 | Jun 7 – Jun 21 | — | — |
| Carrots | — | — | May 3 – May 31 | Jun 29 – Jul 13 |
| Beets | — | — | May 3 – May 31 | Jul 13 – Jul 27 |
| Potatoes | — | — | May 3 – May 24 | — |
| Swiss Chard | — | — | May 10 – Jun 7 | Jul 13 – Jul 27 |
| Cilantro | — | — | May 10 – May 31 | Jul 27 – Aug 17 |
| Green Beans | — | — | May 31 – Jun 21 | Jul 6 – Jul 20 |
| Sweet Corn | — | — | May 31 – Jun 14 | — |
| Sweet Potatoes | — | Jun 7 – Jun 28 | — | — |
| Garlic | — | — | — | Sep 7 – Oct 12 |
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 Rapelje, MT weather station, 2 km away (elevation 4,068 ft (1,240 m)).
Frost dates near Rapelje
- Molt May 24 · Sep 21
- Reed Point May 27 · Sep 14
- Ryegate May 17 · Sep 23
- Broadview May 22 · Sep 15
- Columbus May 27 · Sep 14
- Melville Jun 9 · Sep 7
- Lavina May 22 · Sep 15
- Acton May 4 · Oct 7
- Greycliff May 14 · Sep 26
- Park City May 29 · Sep 15
Frequently asked questions
When is the last frost in Rapelje, MT?
The median last spring frost in Rapelje, MT is May 24. There is still about a 10% chance of frost after June 11, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Rapelje, MT?
The median first fall frost is September 21, with about a 10% chance of frost before September 4.
How long is the growing season in Rapelje, MT?
About 120 days between the median last spring frost and first fall frost.
What planting zone is Rapelje, MT?
Rapelje, MT is in USDA hardiness zone 4b.