When to plant in West Linn, OR
USDA Zone 9aEverything below — frost dates, hardiness zone, and what to plant when in West Linn, Oregon — is derived from the closest NOAA station with complete climate normals.
With about 245 frost-free days, West Linn supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. Zone 9a is warm enough that West Linn can grow subtropical perennials, and the short (or absent) frost period barely limits the annual calendar.
Frost probability
OREGON CITY · 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 West Linn’s own odds, recorded at OREGON CITY.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | May 4 | Apr 15 | Mar 26 | Oct 16 | Oct 31 | Nov 20 |
| 32°F | Apr 11 | Mar 18 | Feb 19 | Oct 30 | Nov 18 | Dec 12 |
| 28°F | Mar 7 | Feb 12 | Jan 1 | Nov 16 | Dec 8 | Jan 5 |
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 West Linn, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 17 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.
West Linn planting FAQ
When is the last spring frost in West Linn, OR?
On average, the last spring frost in West Linn is around March 18 (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 West Linn, OR?
The first fall frost in West Linn typically arrives around November 18 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is West Linn in?
West Linn is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.
How long is the growing season in West Linn?
There are roughly 245 frost-free days in West Linn (a long growing season), running from the average last frost around March 18 to the first fall frost near November 18.
When should I plant tomatoes in West Linn?
In West Linn, start tomato seeds indoors around January 21–February 4, then transplant seedlings outdoors around March 25 once the danger of frost has passed.
Never miss a window in West Linn
An email when it’s time to start seeds, transplant, and sow — timed to West Linn’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Gladstone · 4 km
- Oregon City · 5 km
- Oak Grove · 5 km
- Oatfield · 6 km
- Lake Oswego · 7 km
- Milwaukie · 9 km
- Tualatin · 11 km
- Canby · 12 km
Frost dates recorded at OREGON CITY, 3 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 West Linn, OR — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00356334. Retrieved from https://blissgarden.com/oregon/west-linn.