Frost dates for Anaconda-Deer Lodge County, 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 1
typical year
Safe to plant
June 25
frost is over in 9 of 10 years
First fall frost
September 14
typical year
Growing season
105 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 4 – 18 | – |
| Spinach | – | Apr 20 – May 11 | Jul 20 – Aug 3 |
| Lettuce | – | May 4 – 25 | Jul 20 – Aug 3 |
| Radishes | – | May 4 – Jun 15 | Aug 3 – 17 |
| Onions | – | May 4 – 18 | – |
| Potatoes | Season usually too short. Try a quick variety or row covers. | ||
| Carrots | – | May 11 – Jun 1 | Jun 22 – Jul 6 |
| Beets | – | May 4 – 18 | Jul 6 – 20 |
| Kale | Mar 23 – Apr 6 | May 4 – 18 | Jul 6 – 20 |
| Broccoli | Mar 23 – Apr 6 | May 18 – Jun 1 | Jul 6 – 20 |
| Cabbage | Mar 9 – 23 | May 4 – 18 | Jul 6 – 20 |
| Garlic | – | – | Aug 3 – 24 |
| Warm-season crops | |||
| Tomatoes | Apr 30 – May 14 | Jun 25 – Jul 9 | – |
| Peppers | Apr 23 – May 7 | Jul 2 – 16 | – |
| Cucumbers | – | Jun 25 – Jul 16 | – |
| Zucchini | – | Jun 25 – Jul 23 | – |
| Pumpkins | Season usually too short. Try a quick variety or row covers. | ||
| Green beans | – | Jun 25 – Jul 6 | – |
| Sweet corn | Season usually too short. Try a quick variety or row covers. | ||
| Basil | May 21 – Jun 4 | Jul 2 – 9 | – |
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 | June 25 | June 1 | May 14 |
| Fall frost before | August 31 | September 14 | October 1 |
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 13 (May 30 in a late year), and the first one in fall around September 28.
Towns that use these dates
This is the nearest NOAA station with frost records for 2 towns.
Anaconda-Deer Lodge County, Philipsburg
Where these dates come from
NOAA weather station ANACONDA, MT US (USC00240199), 1991–2020 climate normals. It's the nearest station for 6 zip codes, all within 32 miles:
59711, 59722, 59756, 59762, 59837, 59858
1 of these zip codes are more than 30 miles from the station, so their real frost dates may differ by a week or more.
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.