When to plant in Billings, MT
USDA Zone 5aEverything below — frost dates, hardiness zone, and what to plant when in Billings, Montana — is derived from the closest NOAA station with complete climate normals.
Zone 5a means Billings sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
BILLINGS LOGAN INTL AP · 1991–2020The date the last spring and first fall frost occur, by threshold and probability. A 90% date is later in spring — and earlier in fall — than a 10% date; the 50% · 32°F row is what most gardeners plan around. These are Billings’s own odds, recorded at BILLINGS LOGAN INTL AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 29 | May 15 | May 2 | Sep 16 | Sep 28 | Oct 12 |
| 32°F | May 18 | May 4 | Apr 20 | Sep 26 | Oct 7 | Oct 21 |
| 28°F | May 7 | Apr 21 | Apr 4 | Oct 1 | Oct 16 | Oct 31 |
Download this table as CSV ↓ — every threshold and probability, plus this city’s planting-window dates.
What to plant now
TODAY · JULY 19Full-year planting calendar
Each bar is the exact window to take a planting action in Billings, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 6 km · complete 32°F normalsWhen stations disagree by more than a few days, that spread is real microclimate variation — elevation, water, urban heat. Judge which station best matches your own yard.
Billings planting FAQ
When is the last spring frost in Billings, MT?
Plan for the last spring frost in Billings around May 4 (the date it has a 50% chance of a 32°F freeze). Anything frost-sensitive should go out after it.
When is the first fall frost in Billings, MT?
The first fall frost in Billings typically arrives around October 7 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Billings in?
Billings is in USDA hardiness zone 5a. In zone 5a, winters are cold — pick cold-hardy varieties and protect tender crops.
How long is the growing season in Billings?
There are roughly 156 frost-free days in Billings (a moderate growing season), running from the average last frost around May 4 to the first fall frost near October 7.
When should I plant tomatoes in Billings?
In Billings, start tomato seeds indoors around March 9–March 23, then transplant seedlings outdoors around May 11 once the danger of frost has passed.
Never miss a window in Billings
An email when it’s time to start seeds, transplant, and sow — timed to Billings’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reachFrost dates recorded at BILLINGS LOGAN INTL AP, 2 km from the city center · 1991–2020 NOAA climate normals · zone from the USDA/PRISM 2023 map. How we compute this.
BlissGarden. "When to Plant in Billings, MT — Frost Dates & Zone 5a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00024033. Retrieved from https://blissgarden.com/montana/billings.