When to plant in Milwaukie, OR
USDA Zone 9aMilwaukie, Oregon frost dates, USDA zone, and a full-year planting calendar, drawn from the nearest NOAA station and tuned to the local season.
With about 279 frost-free days, Milwaukie supports back-to-back plantings; stagger sowings every few weeks to keep beds productive spring through fall. In zone 9a, frost is a minor factor for Milwaukie — most perennials thrive, and annual vegetables can go out early and stay late.
Frost probability
PORTLAND KGW-TV · 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 Milwaukie’s own odds, recorded at PORTLAND KGW-TV.
| Threshold | SPRING 10% | SPRING 50% | SPRING 90% | FALL 10% | FALL 50% | FALL 90% |
|---|---|---|---|---|---|---|
| 36°F | Apr 21 | Mar 29 | Mar 7 | Oct 28 | Nov 12 | Dec 1 |
| 32°F | Mar 21 | Feb 25 | Jan 24 | Nov 10 | Dec 1 | Dec 27 |
| 28°F | Feb 26 | Jan 31 | Dec 21 | Nov 25 | Dec 20 | Jan 30 |
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 Milwaukie, drawn to the day from the local frost dates. The dashed line is today.
Nearby weather stations
3 within 14 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.
Milwaukie planting FAQ
When is the last spring frost in Milwaukie, OR?
Plan for the last spring frost in Milwaukie around February 25 (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 Milwaukie, OR?
The first fall frost in Milwaukie typically arrives around December 1 (50% probability at 32°F). Harvest or protect frost-sensitive crops before then.
What hardiness zone is Milwaukie in?
Milwaukie is in USDA hardiness zone 9a. In zone 9a, winters are mild — many tender perennials overwinter here.
How long is the growing season in Milwaukie?
Milwaukie has about 279 frost-free days — a long growing season — between the average last spring frost (February 25) and first fall frost (December 1).
When should I plant tomatoes in Milwaukie?
For Milwaukie, sow tomatoes indoors about December 31–January 14 and move the seedlings out around March 4, after the last spring frost.
Never miss a window in Milwaukie
An email when it’s time to start seeds, transplant, and sow — timed to Milwaukie’s frost dates. Double opt-in, one-click unsubscribe, no spam.
Nearby cities
8 within reach- Oak Grove · 4 km
- Oatfield · 4 km
- Gladstone · 7 km
- Lake Oswego · 7 km
- West Linn · 9 km
- Happy Valley · 9 km
- Portland · 10 km
- Oregon City · 12 km
Frost dates recorded at PORTLAND KGW-TV, 10 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 Milwaukie, OR — Frost Dates & Zone 9a." Frost normals: NOAA NCEI U.S. Climate Normals 1991–2020, station USC00356749. Retrieved from https://blissgarden.com/oregon/milwaukie.