Greycliff, MT frost dates
How Greycliff compares
- In 8 years out of 10, the last spring frost in Greycliff falls between May 2 and May 27, a 25-day window. The first fall frost falls between September 10 and October 8.
- The median last frost is 5 days earlier than the Montana median of May 19.
- Its 135-day growing season is longer than 69% of the 325 Montana places with a regular frost season (state median 125 days).
- The last frost is 11 days later than the zone 5a median of May 3. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 5a chart.
- The weather station records an average of 153 nights a year at or below 32°F.
- Compared with Billings, MT, 98 km away, the last frost here is 10 days later than there and the growing season is 21 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 2 |
| 50% (median) | May 14 |
| 10% (safe for tender plants) | May 27 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 10 |
| 50% (median) | September 26 |
| 90% (late) | October 8 |
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 Greycliff, MT
Greycliff, MT frost dates — last frost May 14, first frost Sep 26, zone 5a. whenisthelastfrost.com
When to plant vegetables in Greycliff, MT
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 19 – Mar 5 | Apr 16 – Apr 30 | — | — |
| Peppers | Mar 5 – Mar 19 | May 28 – Jun 11 | — | — |
| Eggplant | Mar 5 – Mar 19 | May 28 – Jun 11 | — | — |
| Tomatoes | Mar 19 – Apr 2 | May 21 – Jun 4 | — | — |
| Lettuce | Mar 19 – Apr 2 | Apr 23 – May 7 | Apr 16 – May 21 | Aug 1 – Aug 29 |
| Kale | Mar 19 – Apr 2 | Apr 16 – Apr 30 | Apr 16 – Apr 30 | Jul 18 – Aug 8 |
| Broccoli | Mar 19 – Apr 2 | Apr 30 – May 14 | — | Jun 20 – Jul 11 |
| Cabbage | Mar 19 – Apr 2 | Apr 23 – May 7 | — | Jun 20 – Jul 11 |
| Cauliflower | Mar 19 – Apr 2 | Apr 30 – May 14 | — | Jun 20 – Jul 11 |
| Okra | Apr 2 – Apr 16 | Jun 4 – Jun 18 | Jun 4 – Jun 18 | — |
| Basil | Apr 2 – Apr 16 | May 21 – Jun 4 | — | — |
| Peas | — | — | Apr 2 – Apr 23 | Jul 4 – Jul 25 |
| Spinach | — | — | Apr 2 – Apr 23 | Aug 1 – Aug 22 |
| Radishes | — | — | Apr 9 – May 21 | Aug 15 – Sep 5 |
| Cucumbers | Apr 16 – Apr 23 | May 28 – Jun 4 | May 21 – Jun 4 | Jul 11 – Jul 25 |
| Zucchini & Summer Squash | Apr 16 – Apr 23 | — | May 21 – Jun 4 | Jul 18 – Aug 1 |
| Winter Squash & Pumpkins | Apr 16 – Apr 23 | — | May 21 – Jun 4 | — |
| Melons & Watermelon | Apr 16 – Apr 23 | May 28 – Jun 11 | — | — |
| Carrots | — | — | Apr 23 – May 21 | Jul 4 – Jul 18 |
| Beets | — | — | Apr 23 – May 21 | Jul 18 – Aug 1 |
| Potatoes | — | — | Apr 23 – May 14 | — |
| Swiss Chard | — | — | Apr 30 – May 28 | Jul 18 – Aug 1 |
| Cilantro | — | — | Apr 30 – May 21 | Aug 1 – Aug 22 |
| Green Beans | — | — | May 21 – Jun 11 | Jul 11 – Jul 25 |
| Sweet Corn | — | — | May 21 – Jun 4 | — |
| Sweet Potatoes | — | May 28 – Jun 18 | — | — |
| Garlic | — | — | — | Sep 12 – Oct 17 |
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 Big Timber, MT weather station, 15 km away (elevation 4,101 ft (1,250 m)).
Frost dates near Greycliff
- Big Timber May 14 · Sep 26
- Reed Point May 27 · Sep 14
- Mc Leod Jun 1 · Sep 11
- Springdale May 27 · Sep 14
- Nye Jun 1 · Sep 11
- Absarokee May 27 · Sep 14
- Melville Jun 9 · Sep 7
- Fishtail Jun 1 · Sep 11
- Columbus May 27 · Sep 14
- Rapelje May 24 · Sep 21
Frequently asked questions
When is the last frost in Greycliff, MT?
The median last spring frost in Greycliff, MT is May 14. There is still about a 10% chance of frost after May 27, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Greycliff, MT?
The median first fall frost is September 26, with about a 10% chance of frost before September 10.
How long is the growing season in Greycliff, MT?
About 135 days between the median last spring frost and first fall frost.
What planting zone is Greycliff, MT?
Greycliff, MT is in USDA hardiness zone 5a.