Frost dates for Tizer Gardens, 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 18
typical year
Safe to plant
July 3
frost is over in 9 of 10 years
First fall frost
September 5
typical year
Growing season
81 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 21 – Jun 4 | – |
| Spinach | – | May 7 – 28 | Jul 11 – 25 |
| Lettuce | – | May 21 – Jun 11 | Jul 11 – 25 |
| Radishes | – | May 21 – Jul 2 | Jul 25 – Aug 8 |
| Onions | – | May 21 – Jun 4 | – |
| Potatoes | Season usually too short. Try a quick variety or row covers. | ||
| Carrots | – | May 28 – Jun 18 | Jun 13 – 27 |
| Beets | – | May 21 – Jun 4 | Jun 27 – Jul 11 |
| Kale | Apr 9 – 23 | May 21 – Jun 4 | Jun 27 – Jul 11 |
| Broccoli | Apr 9 – 23 | Jun 4 – 18 | Jun 27 – Jul 11 |
| Cabbage | Mar 26 – Apr 9 | May 21 – Jun 4 | Jun 27 – Jul 11 |
| Garlic | – | – | Jul 25 – Aug 15 |
| 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 3 – 24 | – |
| Zucchini | – | Jul 3 – 31 | – |
| 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 | May 29 – Jun 12 | Jul 10 – 17 | – |
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 3 | June 18 | May 30 |
| Fall frost before | August 21 | September 5 | September 18 |
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 29 (June 19 in a late year), and the first one in fall around September 18.
Where these dates come from
NOAA weather station TIZER GARDENS, MT US (USC00248239), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 5 miles:
59634, 59638
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.