Pullman, WA frost dates
Last spring frostMay 6median date
First fall frostSep 29median date
Growing season146 daysfrost-free
Hardiness zone6bZone 6b
How Pullman compares
- In 8 years out of 10, the last spring frost in Pullman falls between April 22 and May 25, a 33-day window. The first fall frost falls between September 9 and October 15.
- The median last frost is 15 days later than the Washington median of Apr 21.
- Its 146-day growing season is longer than 14% of the 491 Washington places with a regular frost season (state median 182 days).
- The last frost is 14 days later than the zone 6b median of Apr 22. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 6b chart.
- The weather station records an average of 127 nights a year at or below 32°F.
- Compared with Spokane, WA, 105 km away, the last frost here is 10 days later than there and the growing season is 26 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 22 |
| 50% (median) | May 6 |
| 10% (safe for tender plants) | May 25 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 9 |
| 50% (median) | September 29 |
| 90% (late) | October 15 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Pullman, WA
Pullman, WA frost dates — last frost May 6, first frost Sep 29, zone 6b. whenisthelastfrost.com
Crop
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Start indoors: Feb 11 to Feb 25Transplant outside: Apr 8 to Apr 22
Start indoors: Feb 25 to Mar 11Transplant outside: May 20 to Jun 3
Start indoors: Feb 25 to Mar 11Transplant outside: May 20 to Jun 3
Start indoors: Mar 11 to Mar 25Transplant outside: May 13 to May 27
Start indoors: Mar 11 to Mar 25Transplant outside: Apr 15 to Apr 29Sow outdoors: Apr 8 to May 13Plant for fall: Aug 4 to Sep 1
Start indoors: Mar 11 to Mar 25Transplant outside: Apr 8 to Apr 22Sow outdoors: Apr 8 to Apr 22Plant for fall: Jul 21 to Aug 11
Start indoors: Mar 11 to Mar 25Transplant outside: Apr 22 to May 6Plant for fall: Jun 23 to Jul 14
Start indoors: Mar 11 to Mar 25Transplant outside: Apr 15 to Apr 29Plant for fall: Jun 23 to Jul 14
Start indoors: Mar 11 to Mar 25Transplant outside: Apr 22 to May 6Plant for fall: Jun 23 to Jul 14
Start indoors: Mar 25 to Apr 8Transplant outside: May 27 to Jun 10Sow outdoors: May 27 to Jun 10
Start indoors: Mar 25 to Apr 8Transplant outside: May 13 to May 27
Sow outdoors: Mar 25 to Apr 15Plant for fall: Jul 7 to Jul 28
Sow outdoors: Mar 25 to Apr 15Plant for fall: Aug 4 to Aug 25
Sow outdoors: Apr 1 to May 13Plant for fall: Aug 18 to Sep 8
Start indoors: Apr 8 to Apr 15Transplant outside: May 20 to May 27Sow outdoors: May 13 to May 27Plant for fall: Jul 14 to Jul 28
Start indoors: Apr 8 to Apr 15Sow outdoors: May 13 to May 27Plant for fall: Jul 21 to Aug 4
Start indoors: Apr 8 to Apr 15Sow outdoors: May 13 to May 27
Start indoors: Apr 8 to Apr 15Transplant outside: May 20 to Jun 3
Sow outdoors: Apr 15 to May 13Plant for fall: Jul 7 to Jul 21
Sow outdoors: Apr 15 to May 13Plant for fall: Jul 21 to Aug 4
Sow outdoors: Apr 15 to May 6
Sow outdoors: Apr 22 to May 20Plant for fall: Jul 21 to Aug 4
Sow outdoors: Apr 22 to May 13Plant for fall: Aug 4 to Aug 25
Sow outdoors: May 13 to Jun 3Plant for fall: Jul 14 to Jul 28
Sow outdoors: May 13 to May 27
Transplant outside: May 20 to Jun 10
Plant for fall: Sep 15 to Oct 20
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Pullman, WA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 11 – Feb 25 | Apr 8 – Apr 22 | — | — |
| Peppers | Feb 25 – Mar 11 | May 20 – Jun 3 | — | — |
| Eggplant | Feb 25 – Mar 11 | May 20 – Jun 3 | — | — |
| Tomatoes | Mar 11 – Mar 25 | May 13 – May 27 | — | — |
| Lettuce | Mar 11 – Mar 25 | Apr 15 – Apr 29 | Apr 8 – May 13 | Aug 4 – Sep 1 |
| Kale | Mar 11 – Mar 25 | Apr 8 – Apr 22 | Apr 8 – Apr 22 | Jul 21 – Aug 11 |
| Broccoli | Mar 11 – Mar 25 | Apr 22 – May 6 | — | Jun 23 – Jul 14 |
| Cabbage | Mar 11 – Mar 25 | Apr 15 – Apr 29 | — | Jun 23 – Jul 14 |
| Cauliflower | Mar 11 – Mar 25 | Apr 22 – May 6 | — | Jun 23 – Jul 14 |
| Okra | Mar 25 – Apr 8 | May 27 – Jun 10 | May 27 – Jun 10 | — |
| Basil | Mar 25 – Apr 8 | May 13 – May 27 | — | — |
| Peas | — | — | Mar 25 – Apr 15 | Jul 7 – Jul 28 |
| Spinach | — | — | Mar 25 – Apr 15 | Aug 4 – Aug 25 |
| Radishes | — | — | Apr 1 – May 13 | Aug 18 – Sep 8 |
| Cucumbers | Apr 8 – Apr 15 | May 20 – May 27 | May 13 – May 27 | Jul 14 – Jul 28 |
| Zucchini & Summer Squash | Apr 8 – Apr 15 | — | May 13 – May 27 | Jul 21 – Aug 4 |
| Winter Squash & Pumpkins | Apr 8 – Apr 15 | — | May 13 – May 27 | — |
| Melons & Watermelon | Apr 8 – Apr 15 | May 20 – Jun 3 | — | — |
| Carrots | — | — | Apr 15 – May 13 | Jul 7 – Jul 21 |
| Beets | — | — | Apr 15 – May 13 | Jul 21 – Aug 4 |
| Potatoes | — | — | Apr 15 – May 6 | — |
| Swiss Chard | — | — | Apr 22 – May 20 | Jul 21 – Aug 4 |
| Cilantro | — | — | Apr 22 – May 13 | Aug 4 – Aug 25 |
| Green Beans | — | — | May 13 – Jun 3 | Jul 14 – Jul 28 |
| Sweet Corn | — | — | May 13 – May 27 | — |
| Sweet Potatoes | — | May 20 – Jun 10 | — | — |
| Garlic | — | — | — | Sep 15 – Oct 20 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Pullman 2 Nw, WA weather station, 3 km away (elevation 2,516 ft (767 m)).
ZIP codes in Pullman: 99163 99164
Frost dates near Pullman
- Albion May 6 · Sep 29
- Colton Apr 29 · Oct 2
- Palouse May 6 · Sep 29
- Colfax May 6 · Sep 29
- Uniontown Apr 6 · Oct 26
- Garfield May 15 · Sep 21
- Steptoe Apr 29 · Oct 4
- Belmont May 7 · Sep 28
- Clarkston Apr 6 · Oct 26
- Farmington May 15 · Sep 21
Frequently asked questions
When is the last frost in Pullman, WA?
The median last spring frost in Pullman, WA is May 6. There is still about a 10% chance of frost after May 25, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Pullman, WA?
The median first fall frost is September 29, with about a 10% chance of frost before September 9.
How long is the growing season in Pullman, WA?
About 146 days between the median last spring frost and first fall frost.
What planting zone is Pullman, WA?
Pullman, WA is in USDA hardiness zone 6b.