When to plant in Altamont, OR
USDA Zone 6bEverything below — frost dates, hardiness zone, and what to plant when in Altamont, Oregon — is derived from the closest NOAA station with complete climate normals.
Altamont's growing season is short at roughly 101 days, so succession planting is limited; lean on transplants over direct sowing for anything slow to mature. Zone 6b means Altamont sees real winter cold, but a good range of perennials survive; the frost dates above govern when annual vegetables go out.
Frost probability
KLAMATH FALLS 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 Altamont’s own odds, recorded at KLAMATH FALLS INTL AP.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 32°F | Jun 26 | Jun 9 | May 22 | Sep 4 | Sep 18 | Oct 1 |
| 28°F | Jun 12 | May 21 | May 2 | Sep 17 | Oct 2 | Oct 17 |
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 Altamont, 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.
Altamont planting FAQ
When is the last spring frost in Altamont, OR?
Altamont's average last spring frost falls near June 9 — the 50% mark at 32°F in the 1991–2020 normals. Hold tender transplants until the risk has passed, then plant out.
When is the first fall frost in Altamont, OR?
The first fall frost in Altamont typically arrives around September 18 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Altamont in?
Altamont is in USDA hardiness zone 6b. In zone 6b, winters are moderate — most common vegetables grow well in season.
How long is the growing season in Altamont?
There are roughly 101 frost-free days in Altamont (a short growing season), running from the average last frost around June 9 to the first fall frost near September 18.
When should I plant tomatoes in Altamont?
In Altamont, start tomato seeds indoors around April 14–April 28, then transplant seedlings outdoors around June 16 once the danger of frost has passed.
Never miss a window in Altamont
An email when it’s time to start seeds, transplant, and sow — timed to Altamont’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Klamath Falls · 5 km
- Ashland · 80 km
- Medford · 94 km
- White City · 95 km
- Central Point · 100 km
- Grants Pass · 135 km
- Roseburg · 175 km
- Shasta Lake · 178 km
Frost dates recorded at KLAMATH FALLS INTL AP, 6 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 Altamont, OR — Frost Dates & Zone 6b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USW00094236. Retrieved from https://blissgarden.com/oregon/altamont.