When to plant in Montana
Most of Montana sees its last spring frost between May 9 and Jun 6, and its first fall frost between Sep 8 and Oct 1. The middle of the state is around May 19 and September 22: that's what the dates below use.
Hardiness zones in Montana: 3b (6%), 4a (18%), 4b (32%), 5a (28%), 5b (8%), 6a (8%).
Planting dates for common crops
| Crop | Start indoors | Plant outside | Harvest | Plant for fall |
|---|---|---|---|---|
| Tomato | Apr 16 | Jun 4 – Jun 18 | Aug 13 – Sep 22 | — |
| Pepper | Apr 2 | Jun 4 – Jun 18 | Aug 18 – Sep 22 | — |
| Cucumber | — | Jun 4 – Jun 18 | Jul 29 – Sep 16 | — |
| Zucchini / Summer squash | — | Jun 4 – Jun 18 | Jul 24 – Sep 22 | — |
| Winter squash | — | Jun 4 – Jun 18 | Sep 7 – Sep 22 | — |
| Green beans (bush) | — | Jun 4 – Jun 18 | Jul 29 – Sep 9 | — |
| Peas | — | Apr 7 – Apr 21 | Jun 6 – Jul 11 | Jul 3 – Jul 17 |
| Sweet corn | — | Jun 4 – Jun 18 | Aug 18 – Sep 15 | — |
| Lettuce | — | Apr 21 – May 5 | Jun 5 – Jul 17 | Jul 25 – Aug 8 |
| Spinach | — | Apr 7 – Apr 21 | May 17 – Jun 28 | Aug 13 – Aug 27 |
| Kale | Mar 10 | Apr 21 – May 5 | Jun 15 – Sep 7 | Aug 12 – Aug 26 |
| Broccoli | Mar 17 | Apr 28 – May 12 | Jun 27 – Aug 1 | Jul 17 – Jul 31 |
| Cabbage | Mar 10 | Apr 21 – May 5 | Jun 30 – Aug 4 | Jul 14 – Jul 28 |
| Carrot | — | Apr 28 – May 12 | Jul 7 – Aug 18 | Jul 14 – Jul 28 |
| Beet | — | Apr 28 – May 12 | Jun 22 – Aug 3 | Jul 22 – Aug 5 |
| Radish | — | Apr 14 – Apr 28 | May 9 – Jun 6 | Aug 14 – Aug 28 |
| Onion (sets) | — | Apr 14 – Apr 28 | Jul 23 – Aug 27 | — |
| Garlic | — | Sep 15 – Oct 6 (fall) | Jul 14 – Aug 4 next year | — |
| Potato | — | Apr 28 – May 12 | Jul 27 – Aug 31 | — |
| Sweet potato Tight season: harvest may be cut short by frost. Choose an early variety. | Apr 28 | Jun 9 – Jun 23 | Sep 17 – Sep 22 | — |
| Watermelon | — | Jun 9 – Jun 23 | Sep 2 – Sep 22 | — |
| Basil | Apr 23 | Jun 4 – Jun 18 | Jul 4 – Sep 22 | — |
| Strawberry (June-bearing) | — | Apr 28 – May 12 | Jun 16 – Jul 14 (once established) | — |
| Sunflower | — | Jun 4 – Jun 18 | Aug 23 – Sep 22 | — |
Dates for a typical spot in Montana. Colder and higher places plant later, warmer ones earlier: enter your ZIP code for yours, or see the calendar for your zone.
Frost dates around Montana
| Place | Zone | Last frost | First frost |
|---|---|---|---|
| Billings | 5a | May 12 | Sep 25 |
| Missoula | 5b | May 10 | Oct 1 |
| Helena | 4b | May 9 | Sep 30 |
| Bozeman | 5a | May 26 | Sep 22 |
| Butte | 5a | Jun 13 | Sep 5 |
| Great Falls | 4b | May 6 | Oct 1 |
| Kalispell | 5b | May 31 | Sep 10 |
| Ashland | 4b | May 26 | Sep 19 |
| Roundup | 4b | May 20 | Sep 21 |
| Absarokee | 5a | May 27 | Sep 14 |
Average dates from the nearest NOAA weather stations (1991–2020). Click a place for its full planting calendar.