Frost dates for West Yellowstone, MT
When the last spring frost and first fall frost usually come, and when to plant, from 30 years of NOAA weather records.
Last spring frost
June 15
typical year
Safe to plant
July 7
frost is over in 9 of 10 years
First fall frost
September 10
typical year
Growing season
87 days
frost-free, typical year
Frost watch this week
Tonight's and the next six nights' lows from the National Weather Service forecast for the station's location. Frost: 32°F or colder. Possible frost: 33–36°F, mostly in low spots on clear, still nights.
When to plant
Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.
| Crop | Start indoors | Plant outside | Fall planting |
|---|---|---|---|
| Cool-season crops | |||
| Peas | – | May 18 – Jun 1 | – |
| Spinach | – | May 4 – 25 | Jul 16 – 30 |
| Lettuce | – | May 18 – Jun 8 | Jul 16 – 30 |
| Radishes | – | May 18 – Jun 29 | Jul 30 – Aug 13 |
| Onions | – | May 18 – Jun 1 | – |
| Potatoes | Season usually too short. Try a quick variety or row covers. | ||
| Carrots | – | May 25 – Jun 15 | Jun 18 – Jul 2 |
| Beets | – | May 18 – Jun 1 | Jul 2 – 16 |
| Kale | Apr 6 – 20 | May 18 – Jun 1 | Jul 2 – 16 |
| Broccoli | Apr 6 – 20 | Jun 1 – 15 | Jul 2 – 16 |
| Cabbage | Mar 23 – Apr 6 | May 18 – Jun 1 | Jul 2 – 16 |
| Garlic | – | – | Jul 30 – Aug 20 |
| Warm-season crops | |||
| Tomatoes | Season usually too short. Try a quick variety or row covers. | ||
| Peppers | Season usually too short. Try a quick variety or row covers. | ||
| Cucumbers | – | Jul 7 – 28 | – |
| Zucchini | – | Jul 7 – Aug 4 | – |
| Pumpkins | Season usually too short. Try a quick variety or row covers. | ||
| Green beans | Season usually too short. Try a quick variety or row covers. | ||
| Sweet corn | Season usually too short. Try a quick variety or row covers. | ||
| Basil | Jun 2 – 16 | Jul 14 – 21 | – |
Onions: from sets. Green beans: until 10 weeks before the first fall frost. Garlic: harvest next summer.
The year at a glance
Start indoors Plant outside Fall planting
The chance of frost, by date
| 1 year in 10 | Half of years | 9 years in 10 | |
|---|---|---|---|
| Spring frost after | July 7 | June 15 | May 29 |
| Fall frost before | August 25 | September 10 | September 27 |
Frost here means 32°F or colder. Read across: in 1 year in 10, spring frost carries on past the first date, which is why that date is the safe-to-plant date.
Hard freeze (28°F)
A hard freeze kills most garden plants, even hardy ones. The last one in spring usually comes around May 24 (June 16 in a late year), and the first one in fall around September 26.
Towns that use these dates
This is the nearest NOAA station with frost records for 2 towns.
West Yellowstone, Island Park, ID
Where these dates come from
NOAA weather station HEBGEN DAM, MT US (USC00244038), 1991–2020 climate normals. It's the nearest station for 4 zip codes, all within 27 miles:
59720, 59758, 83429, 83433
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.