Walla Walla, WA frost dates
Last spring frostMar 27median date
First fall frostOct 31median date
Growing season218 daysfrost-free
Hardiness zone7aZone 7a
How Walla Walla compares
- In 8 years out of 10, the last spring frost in Walla Walla falls between March 3 and April 22, a 50-day window. The first fall frost falls between October 15 and November 17.
- The median last frost is 25 days earlier than the Washington median of Apr 21.
- Its 218-day growing season is longer than 73% of the 491 Washington places with a regular frost season (state median 182 days).
- The last frost is 20 days earlier than the zone 7a median of Apr 16. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 7a chart.
- The weather station records an average of 70 nights a year at or below 32°F.
- Compared with Pasco, WA, 62 km away, the last frost here is 31 days earlier than there and the growing season is 51 days longer.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | March 3 |
| 50% (median) | March 27 |
| 10% (safe for tender plants) | April 22 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 15 |
| 50% (median) | October 31 |
| 90% (late) | November 17 |
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 Walla Walla, WA
Walla Walla, WA frost dates — last frost Mar 27, first frost Oct 31, zone 7a. whenisthelastfrost.com
Crop
JFMAMJJASOND
Start indoors: Jan 2 to Jan 16Transplant outside: Feb 27 to Mar 13
Start indoors: Jan 16 to Jan 30Transplant outside: Apr 10 to Apr 24
Start indoors: Jan 16 to Jan 30Transplant outside: Apr 10 to Apr 24
Start indoors: Jan 30 to Feb 13Transplant outside: Apr 3 to Apr 17
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 6 to Mar 20Sow outdoors: Feb 27 to Apr 3Plant for fall: Sep 5 to Oct 3
Start indoors: Jan 30 to Feb 13Transplant outside: Feb 27 to Mar 13Sow outdoors: Feb 27 to Mar 13Plant for fall: Aug 22 to Sep 12
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 13 to Mar 27Plant for fall: Jul 25 to Aug 15
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 6 to Mar 20Plant for fall: Jul 25 to Aug 15
Start indoors: Jan 30 to Feb 13Transplant outside: Mar 13 to Mar 27Plant for fall: Jul 25 to Aug 15
Start indoors: Feb 13 to Feb 27Transplant outside: Apr 17 to May 1Sow outdoors: Apr 17 to May 1
Start indoors: Feb 13 to Feb 27Transplant outside: Apr 3 to Apr 17
Sow outdoors: Feb 13 to Mar 6Plant for fall: Aug 8 to Aug 29
Sow outdoors: Feb 13 to Mar 6Plant for fall: Sep 5 to Sep 26
Sow outdoors: Feb 20 to Apr 3Plant for fall: Sep 19 to Oct 10
Start indoors: Feb 27 to Mar 6Transplant outside: Apr 10 to Apr 17Sow outdoors: Apr 3 to Apr 17Plant for fall: Aug 15 to Aug 29
Start indoors: Feb 27 to Mar 6Sow outdoors: Apr 3 to Apr 17Plant for fall: Aug 22 to Sep 5
Start indoors: Feb 27 to Mar 6Sow outdoors: Apr 3 to Apr 17
Start indoors: Feb 27 to Mar 6Transplant outside: Apr 10 to Apr 24
Sow outdoors: Mar 6 to Apr 3Plant for fall: Aug 8 to Aug 22
Sow outdoors: Mar 6 to Apr 3Plant for fall: Aug 22 to Sep 5
Sow outdoors: Mar 6 to Mar 27
Sow outdoors: Mar 13 to Apr 10Plant for fall: Aug 22 to Sep 5
Sow outdoors: Mar 13 to Apr 3Plant for fall: Sep 5 to Sep 26
Sow outdoors: Apr 3 to Apr 24Plant for fall: Aug 15 to Aug 29
Sow outdoors: Apr 3 to Apr 17
Transplant outside: Apr 10 to May 1
Plant for fall: Oct 17 to Nov 21
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Walla Walla, WA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 2 – Jan 16 | Feb 27 – Mar 13 | — | — |
| Peppers | Jan 16 – Jan 30 | Apr 10 – Apr 24 | — | — |
| Eggplant | Jan 16 – Jan 30 | Apr 10 – Apr 24 | — | — |
| Tomatoes | Jan 30 – Feb 13 | Apr 3 – Apr 17 | — | — |
| Lettuce | Jan 30 – Feb 13 | Mar 6 – Mar 20 | Feb 27 – Apr 3 | Sep 5 – Oct 3 |
| Kale | Jan 30 – Feb 13 | Feb 27 – Mar 13 | Feb 27 – Mar 13 | Aug 22 – Sep 12 |
| Broccoli | Jan 30 – Feb 13 | Mar 13 – Mar 27 | — | Jul 25 – Aug 15 |
| Cabbage | Jan 30 – Feb 13 | Mar 6 – Mar 20 | — | Jul 25 – Aug 15 |
| Cauliflower | Jan 30 – Feb 13 | Mar 13 – Mar 27 | — | Jul 25 – Aug 15 |
| Okra | Feb 13 – Feb 27 | Apr 17 – May 1 | Apr 17 – May 1 | — |
| Basil | Feb 13 – Feb 27 | Apr 3 – Apr 17 | — | — |
| Peas | — | — | Feb 13 – Mar 6 | Aug 8 – Aug 29 |
| Spinach | — | — | Feb 13 – Mar 6 | Sep 5 – Sep 26 |
| Radishes | — | — | Feb 20 – Apr 3 | Sep 19 – Oct 10 |
| Cucumbers | Feb 27 – Mar 6 | Apr 10 – Apr 17 | Apr 3 – Apr 17 | Aug 15 – Aug 29 |
| Zucchini & Summer Squash | Feb 27 – Mar 6 | — | Apr 3 – Apr 17 | Aug 22 – Sep 5 |
| Winter Squash & Pumpkins | Feb 27 – Mar 6 | — | Apr 3 – Apr 17 | — |
| Melons & Watermelon | Feb 27 – Mar 6 | Apr 10 – Apr 24 | — | — |
| Carrots | — | — | Mar 6 – Apr 3 | Aug 8 – Aug 22 |
| Beets | — | — | Mar 6 – Apr 3 | Aug 22 – Sep 5 |
| Potatoes | — | — | Mar 6 – Mar 27 | — |
| Swiss Chard | — | — | Mar 13 – Apr 10 | Aug 22 – Sep 5 |
| Cilantro | — | — | Mar 13 – Apr 3 | Sep 5 – Sep 26 |
| Green Beans | — | — | Apr 3 – Apr 24 | Aug 15 – Aug 29 |
| Sweet Corn | — | — | Apr 3 – Apr 17 | — |
| Sweet Potatoes | — | Apr 10 – May 1 | — | — |
| Garlic | — | — | — | Oct 17 – Nov 21 |
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 Walla Walla Rgnl Ap, WA weather station, 5 km away (elevation 1,165 ft (355 m)).
Frost dates near Walla Walla
- College Place May 2 · Oct 1
- Dixie Mar 27 · Oct 31
- Touchet May 2 · Oct 1
- Waitsburg Apr 28 · Oct 13
- Prescott Mar 27 · Oct 31
- Dayton Apr 28 · Oct 13
- Wallula Apr 7 · Oct 22
- Burbank Apr 7 · Oct 22
- Starbuck Apr 28 · Oct 13
- Pasco Apr 27 · Oct 11
Frequently asked questions
When is the last frost in Walla Walla, WA?
The median last spring frost in Walla Walla, WA is March 27. There is still about a 10% chance of frost after April 22, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Walla Walla, WA?
The median first fall frost is October 31, with about a 10% chance of frost before October 15.
How long is the growing season in Walla Walla, WA?
About 218 days between the median last spring frost and first fall frost.
What planting zone is Walla Walla, WA?
Walla Walla, WA is in USDA hardiness zone 7a.