Jordan, MT frost dates
How Jordan compares
- In 8 years out of 10, the last spring frost in Jordan falls between May 8 and June 2, a 25-day window. The first fall frost falls between September 4 and October 1.
- The median last frost is 2 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 9 days later than the zone 4a median of May 12. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4a chart.
- The weather station records an average of 190 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 8 |
| 50% (median) | May 21 |
| 10% (safe for tender plants) | June 2 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 4 |
| 50% (median) | September 18 |
| 90% (late) | October 1 |
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 Jordan, MT
Jordan, MT frost dates — last frost May 21, first frost Sep 18, zone 4a. whenisthelastfrost.com
When to plant vegetables in Jordan, MT
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 26 – Mar 12 | Apr 23 – May 7 | — | — |
| Peppers | Mar 12 – Mar 26 | Jun 4 – Jun 18 | — | — |
| Eggplant | Mar 12 – Mar 26 | Jun 4 – Jun 18 | — | — |
| Tomatoes | Mar 26 – Apr 9 | May 28 – Jun 11 | — | — |
| Lettuce | Mar 26 – Apr 9 | Apr 30 – May 14 | Apr 23 – May 28 | Jul 24 – Aug 21 |
| Kale | Mar 26 – Apr 9 | Apr 23 – May 7 | Apr 23 – May 7 | Jul 10 – Jul 31 |
| Broccoli | Mar 26 – Apr 9 | May 7 – May 21 | — | Jun 12 – Jul 3 |
| Cabbage | Mar 26 – Apr 9 | Apr 30 – May 14 | — | Jun 12 – Jul 3 |
| Cauliflower | Mar 26 – Apr 9 | May 7 – May 21 | — | Jun 12 – Jul 3 |
| Okra | Apr 9 – Apr 23 | Jun 11 – Jun 25 | Jun 11 – Jun 25 | — |
| Basil | Apr 9 – Apr 23 | May 28 – Jun 11 | — | — |
| Peas | — | — | Apr 9 – Apr 30 | Jun 26 – Jul 17 |
| Spinach | — | — | Apr 9 – Apr 30 | Jul 24 – Aug 14 |
| Radishes | — | — | Apr 16 – May 28 | Aug 7 – Aug 28 |
| Cucumbers | Apr 23 – Apr 30 | Jun 4 – Jun 11 | May 28 – Jun 11 | Jul 3 – Jul 17 |
| Zucchini & Summer Squash | Apr 23 – Apr 30 | — | May 28 – Jun 11 | Jul 10 – Jul 24 |
| Winter Squash & Pumpkins | Apr 23 – Apr 30 | — | May 28 – Jun 11 | — |
| Melons & Watermelon | Apr 23 – Apr 30 | Jun 4 – Jun 18 | — | — |
| Carrots | — | — | Apr 30 – May 28 | Jun 26 – Jul 10 |
| Beets | — | — | Apr 30 – May 28 | Jul 10 – Jul 24 |
| Potatoes | — | — | Apr 30 – May 21 | — |
| Swiss Chard | — | — | May 7 – Jun 4 | Jul 10 – Jul 24 |
| Cilantro | — | — | May 7 – May 28 | Jul 24 – Aug 14 |
| Green Beans | — | — | May 28 – Jun 18 | Jul 3 – Jul 17 |
| Sweet Corn | — | — | May 28 – Jun 11 | — |
| Sweet Potatoes | — | Jun 4 – Jun 25 | — | — |
| Garlic | — | — | — | Sep 4 – Oct 9 |
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 Jordan, MT weather station, about 1 km away (elevation 2,621 ft (799 m)).
Frost dates near Jordan
- Brusett May 18 · Sep 20
- Cohagen May 25 · Sep 14
- Sand Springs May 5 · Oct 4
- Mosby May 5 · Oct 4
- Fort Peck May 8 · Oct 1
- Angela May 15 · Sep 25
- Brockway May 20 · Sep 19
- Ingomar May 21 · Sep 19
- Sumatra May 10 · Sep 29
- Circle May 17 · Sep 22
Frequently asked questions
When is the last frost in Jordan, MT?
The median last spring frost in Jordan, MT is May 21. There is still about a 10% chance of frost after June 2, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Jordan, MT?
The median first fall frost is September 18, with about a 10% chance of frost before September 4.
How long is the growing season in Jordan, MT?
About 120 days between the median last spring frost and first fall frost.
What planting zone is Jordan, MT?
Jordan, MT is in USDA hardiness zone 4a.