Last frost date in Pullman, WA
The average last frost in Pullman is May 6. By May 25 the chance of another 32°F night drops to 1 in 10. The first fall frost usually arrives about September 29, which leaves 143 frost-free days. An early freeze before September 9 happens one year in ten.
- Safe after (10% risk)
- May 25
- Average first frost
- Sep 29
- Frost-free season
- 143 days
- Hard freeze (28°F) ends
- Apr 19
Hard freeze likely Fri night, low 28°F
National Weather Service forecast, updated Oct 22, 12:57 UTC
- ThuOct 2240°
- FriOct 2328°hard freeze
- SatOct 2432°frost
- SunOct 2532°frost
- MonOct 2631°frost
- TueOct 2730°frost
Planting calendar for Pullman
Windows count forward or back from the average frost dates above. Click a crop for dates across Washington.
TomatoesMay 13–May 27
PumpkinsMay 20–Jun 3
SunflowersMay 6–May 27
CucumbersMay 20–May 27
CornMay 13–May 27
Sweet potatoesMay 27–Jun 10
WatermelonMay 20–Jun 3
Green beansMay 13–Jun 3
ZucchiniMay 13–May 27
OkraMay 27–Jun 10
PeppersMay 20–Jun 3
BasilMay 13–May 27
Butternut squashMay 13–May 27
CantaloupeMay 20–Jun 3
EggplantMay 20–Jun 3
PotatoesApr 8–Apr 22
OnionsMar 25–Apr 15
CarrotsApr 15–May 20
LettuceApr 22–May 13
BroccoliApr 8–Apr 22
BeetsApr 8–May 20
PeasMar 25–Apr 8
CabbageApr 8–Apr 22
RadishesApr 1–May 13
Brussels sproutsApr 22–May 6
SpinachMar 25–Apr 15
CilantroApr 22–May 13
KaleApr 8–Apr 22
Collard greensApr 8–Apr 22
TurnipsApr 8–Apr 22
DillMay 6–May 20
CeleryMay 13–May 20
CauliflowerApr 22–May 6
LeeksApr 22–May 6
Swiss chardApr 22–May 20
ParsleyApr 22–May 13
Tulip bulbsSep 15–Oct 20
GarlicSep 8–Oct 13
Daffodil bulbsSep 1–Oct 13
StrawberriesApr 8–Apr 22
AsparagusApr 8–Apr 22Frost probabilities
| Threshold | Spring, 90% chance later | Spring, 50% | Spring, 10% | Fall, 10% chance earlier | Fall, 50% | Fall, 90% |
|---|---|---|---|---|---|---|
| Light frost, 32°F | Apr 22 | May 6 | May 25 | Sep 9 | Sep 29 | Oct 15 |
| Hard freeze, 28°F | Mar 27 | Apr 19 | May 7 | Sep 26 | Oct 12 | Nov 2 |
Read the spring 10% column as the date after which only one year in ten still gets frost. That is the safer date for tomatoes, peppers and basil.
Where these numbers come from
NOAA station Pullman 2 NW (USC00456789) sits 2.1 miles from the center of Pullman at 2,515 feet. Its averages cover 1991 to 2020. Low spots, valleys and open fields can keep getting frost a week or two after the station stops; city centers and lakeshores usually get less of it.
Questions
When is the last frost in Pullman, WA?
The average last frost date in Pullman is May 6, based on NOAA 1991–2020 climate normals. There is a 10% chance of frost after May 25.
When is the first frost in Pullman?
The first frost in fall usually comes around September 29. One year in ten it arrives before September 9.
How long is the growing season in Pullman?
About 143 days between the average last and first frost.
When should I plant tomatoes in Pullman?
Plant tomato seedlings outside from May 13 to May 27. Start seeds indoors six to eight weeks earlier.
Nearby in Washington
- Spokane ValleyApr 26
- SpokaneApr 26
- Walla WallaMar 27
- PascoApr 27
- KennewickMar 28
- Moses LakeApr 27
- RichlandApr 6
- WenatcheeApr 4
- YakimaApr 8
- EllensburgMay 8
- Maple ValleyApr 20
- IssaquahMar 13