Frost dates for Portland, OR
When the last spring frost and first fall frost usually come, and when to plant, from 30 years of NOAA weather records.
Last spring frost
February 25
typical year
Safe to plant
March 21
frost is over in 9 of 10 years
First fall frost
December 1
typical year
Growing season
280 days
frost-free, typical year
Frost watch this week
Tonight's and the next six nights' lows from the National Weather Service forecast for the station's location. Frost: 32°F or colder. Possible frost: 33–36°F, mostly in low spots on clear, still nights.
When to plant
Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.
| Crop | Start indoors | Plant outside | Fall planting |
|---|---|---|---|
| Cool-season crops | |||
| Peas | – | Jan 28 – Feb 11 | – |
| Spinach | – | Jan 14 – Feb 4 | Oct 6 – 20 |
| Lettuce | – | Jan 28 – Feb 18 | Oct 6 – 20 |
| Radishes | – | Jan 28 – Mar 11 | Oct 20 – Nov 3 |
| Onions | – | Jan 28 – Feb 11 | – |
| Potatoes | – | Feb 4 – 18 | – |
| Carrots | – | Feb 4 – 25 | Sep 8 – 22 |
| Beets | – | Jan 28 – Feb 11 | Sep 22 – Oct 6 |
| Kale | Dec 17 – 31 | Jan 28 – Feb 11 | Sep 22 – Oct 6 |
| Broccoli | Dec 17 – 31 | Feb 11 – 25 | Sep 22 – Oct 6 |
| Cabbage | Dec 3 – 17 | Jan 28 – Feb 11 | Sep 22 – Oct 6 |
| Garlic | – | – | Oct 20 – Nov 10 |
| Warm-season crops | |||
| Tomatoes | Jan 24 – Feb 7 | Mar 21 – Apr 4 | – |
| Peppers | Jan 17 – 31 | Mar 28 – Apr 11 | – |
| Cucumbers | – | Mar 21 – Apr 11 | – |
| Zucchini | – | Mar 21 – Apr 18 | – |
| Pumpkins | – | Mar 21 – Apr 11 | – |
| Green beans | – | Mar 21 – Sep 22 | – |
| Sweet corn | – | Mar 21 – Apr 18 | – |
| Basil | Feb 14 – 28 | Mar 28 – Apr 4 | – |
Onions: from sets. Green beans: until 10 weeks before the first fall frost. Garlic: harvest next summer.
The year at a glance
Start indoors Plant outside Fall planting
The chance of frost, by date
| 1 year in 10 | Half of years | 9 years in 10 | |
|---|---|---|---|
| Spring frost after | March 21 | February 25 | January 24 |
| Fall frost before | November 10 | December 1 | December 27 |
Frost here means 32°F or colder. Read across: in 1 year in 10, spring frost carries on past the first date, which is why that date is the safe-to-plant date.
Hard freeze (28°F)
A hard freeze kills most garden plants, even hardy ones. The last one in spring usually comes around January 31 (February 26 in a late year), and the first one in fall around December 20.
Towns that use these dates
This is the nearest NOAA station with frost records for 2 towns.
Portland, Milwaukie
Where these dates come from
NOAA weather station PORTLAND KGW-TV, OR US (USC00356749), 1991–2020 climate normals. It's the nearest station for 16 zip codes, all within 5 miles:
97201, 97202, 97204, 97205, 97206, 97208, 97209, 97210, 97212, 97214, 97219, 97221, 97227, 97232, 97239, 97258
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.