When to plant in Happy Valley, OR
USDA Zone 8bEverything below — frost dates, hardiness zone, and what to plant when in Happy Valley, Oregon — is derived from the closest NOAA station with complete climate normals.
A generous ~245-day season lets Happy Valley gardeners direct-sow more and still ripen long-maturity crops like melons and winter squash. Zone 8b means many perennials and even some tender shrubs overwinter in Happy Valley, while your frost dates still decide when annuals go out.
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 Happy Valley’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 Happy Valley, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 15 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.
Happy Valley planting FAQ
When is the last spring frost in Happy Valley, OR?
On average, the last spring frost in Happy Valley 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 Happy Valley, OR?
The first fall frost in Happy Valley typically arrives around November 18 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Happy Valley in?
Happy Valley is in USDA hardiness zone 8b. In zone 8b, winters are mild — many tender perennials overwinter here.
How long is the growing season in Happy Valley?
There are roughly 245 frost-free days in Happy Valley (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 Happy Valley?
In Happy Valley, 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 Happy Valley
An email when it’s time to start seeds, transplant, and sow — timed to Happy Valley’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reachFrost dates recorded at OREGON CITY, 11 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 Happy Valley, OR — Frost Dates & Zone 8b." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00356334. Retrieved from https://blissgarden.com/oregon/happy-valley.