When to plant in Blackfoot, ID
USDA Zone 5bHere are the average frost dates, USDA hardiness zone, and a month-by-month planting calendar for Blackfoot, Idaho — all computed from Blackfoot's nearest NOAA weather station.
In zone 5b, Blackfoot gardeners can grow many hardy perennials, while the last and first frost still dictate the annual vegetable calendar.
Frost probability
BLACKFOOT FIRE DEPT · 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 Blackfoot’s own odds, recorded at BLACKFOOT FIRE DEPT.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Jun 14 | May 23 | May 8 | Sep 4 | Sep 21 | Oct 5 |
| 32°F | May 22 | May 5 | Apr 23 | Sep 16 | Oct 3 | Oct 18 |
| 28°F | May 4 | Apr 22 | Apr 6 | Sep 30 | 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 Blackfoot, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 34 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.
Blackfoot planting FAQ
When is the last spring frost in Blackfoot, ID?
On average, the last spring frost in Blackfoot is around May 5 (50% probability at 32°F, from 1991–2020 NOAA normals). Wait until after this date to set out tender plants like tomatoes and peppers.
When is the first fall frost in Blackfoot, ID?
The first fall frost in Blackfoot typically arrives around October 3 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Blackfoot in?
Blackfoot is in USDA hardiness zone 5b. In zone 5b, winters are cold — pick cold-hardy varieties and protect tender crops.
How long is the growing season in Blackfoot?
Blackfoot has about 151 frost-free days — a moderate growing season — between the average last spring frost (May 5) and first fall frost (October 3).
When should I plant tomatoes in Blackfoot?
For Blackfoot, sow tomatoes indoors about March 10–March 24 and move the seedlings out around May 12, after the last spring frost.
Never miss a window in Blackfoot
An email when it’s time to start seeds, transplant, and sow — timed to Blackfoot’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Chubbuck · 31 km
- Pocatello · 37 km
- Idaho Falls · 41 km
- Ammon · 44 km
- Rexburg · 83 km
- Jackson · 131 km
- Burley · 139 km
- Smithfield · 157 km
Frost dates recorded at BLACKFOOT FIRE DEPT, 0 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 Blackfoot, ID — Frost Dates & Zone 5b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00100915. Retrieved from https://blissgarden.com/idaho/blackfoot.