Kittitas, WA frost dates
Last spring frostMay 8median date
First fall frostOct 2median date
Growing season147 daysfrost-free
Hardiness zone6bZone 6b
How Kittitas compares
- In 8 years out of 10, the last spring frost in Kittitas falls between April 25 and May 25, a 30-day window. The first fall frost falls between September 20 and October 14.
- The median last frost is 17 days later than the Washington median of Apr 21.
- Its 147-day growing season is longer than 16% of the 491 Washington places with a regular frost season (state median 182 days).
- The last frost is 16 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 155 nights a year at or below 32°F.
- Compared with Yakima, WA, 46 km away, the last frost here is 30 days later than there and the growing season is 51 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 25 |
| 50% (median) | May 8 |
| 10% (safe for tender plants) | May 25 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 20 |
| 50% (median) | October 2 |
| 90% (late) | October 14 |
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 Kittitas, WA
Kittitas, WA frost dates — last frost May 8, first frost Oct 2, zone 6b. whenisthelastfrost.com
Crop
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Start indoors: Feb 13 to Feb 27Transplant outside: Apr 10 to Apr 24
Start indoors: Feb 27 to Mar 13Transplant outside: May 22 to Jun 5
Start indoors: Feb 27 to Mar 13Transplant outside: May 22 to Jun 5
Start indoors: Mar 13 to Mar 27Transplant outside: May 15 to May 29
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 17 to May 1Sow outdoors: Apr 10 to May 15Plant for fall: Aug 7 to Sep 4
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 10 to Apr 24Sow outdoors: Apr 10 to Apr 24Plant for fall: Jul 24 to Aug 14
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 24 to May 8Plant for fall: Jun 26 to Jul 17
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 17 to May 1Plant for fall: Jun 26 to Jul 17
Start indoors: Mar 13 to Mar 27Transplant outside: Apr 24 to May 8Plant for fall: Jun 26 to Jul 17
Start indoors: Mar 27 to Apr 10Transplant outside: May 29 to Jun 12Sow outdoors: May 29 to Jun 12
Start indoors: Mar 27 to Apr 10Transplant outside: May 15 to May 29
Sow outdoors: Mar 27 to Apr 17Plant for fall: Jul 10 to Jul 31
Sow outdoors: Mar 27 to Apr 17Plant for fall: Aug 7 to Aug 28
Sow outdoors: Apr 3 to May 15Plant for fall: Aug 21 to Sep 11
Start indoors: Apr 10 to Apr 17Transplant outside: May 22 to May 29Sow outdoors: May 15 to May 29Plant for fall: Jul 17 to Jul 31
Start indoors: Apr 10 to Apr 17Sow outdoors: May 15 to May 29Plant for fall: Jul 24 to Aug 7
Start indoors: Apr 10 to Apr 17Sow outdoors: May 15 to May 29
Start indoors: Apr 10 to Apr 17Transplant outside: May 22 to Jun 5
Sow outdoors: Apr 17 to May 15Plant for fall: Jul 10 to Jul 24
Sow outdoors: Apr 17 to May 15Plant for fall: Jul 24 to Aug 7
Sow outdoors: Apr 17 to May 8
Sow outdoors: Apr 24 to May 22Plant for fall: Jul 24 to Aug 7
Sow outdoors: Apr 24 to May 15Plant for fall: Aug 7 to Aug 28
Sow outdoors: May 15 to Jun 5Plant for fall: Jul 17 to Jul 31
Sow outdoors: May 15 to May 29
Transplant outside: May 22 to Jun 12
Plant for fall: Sep 18 to Oct 23
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Kittitas, WA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 13 – Feb 27 | Apr 10 – Apr 24 | — | — |
| Peppers | Feb 27 – Mar 13 | May 22 – Jun 5 | — | — |
| Eggplant | Feb 27 – Mar 13 | May 22 – Jun 5 | — | — |
| Tomatoes | Mar 13 – Mar 27 | May 15 – May 29 | — | — |
| Lettuce | Mar 13 – Mar 27 | Apr 17 – May 1 | Apr 10 – May 15 | Aug 7 – Sep 4 |
| Kale | Mar 13 – Mar 27 | Apr 10 – Apr 24 | Apr 10 – Apr 24 | Jul 24 – Aug 14 |
| Broccoli | Mar 13 – Mar 27 | Apr 24 – May 8 | — | Jun 26 – Jul 17 |
| Cabbage | Mar 13 – Mar 27 | Apr 17 – May 1 | — | Jun 26 – Jul 17 |
| Cauliflower | Mar 13 – Mar 27 | Apr 24 – May 8 | — | Jun 26 – Jul 17 |
| Okra | Mar 27 – Apr 10 | May 29 – Jun 12 | May 29 – Jun 12 | — |
| Basil | Mar 27 – Apr 10 | May 15 – May 29 | — | — |
| Peas | — | — | Mar 27 – Apr 17 | Jul 10 – Jul 31 |
| Spinach | — | — | Mar 27 – Apr 17 | Aug 7 – Aug 28 |
| Radishes | — | — | Apr 3 – May 15 | Aug 21 – Sep 11 |
| Cucumbers | Apr 10 – Apr 17 | May 22 – May 29 | May 15 – May 29 | Jul 17 – Jul 31 |
| Zucchini & Summer Squash | Apr 10 – Apr 17 | — | May 15 – May 29 | Jul 24 – Aug 7 |
| Winter Squash & Pumpkins | Apr 10 – Apr 17 | — | May 15 – May 29 | — |
| Melons & Watermelon | Apr 10 – Apr 17 | May 22 – Jun 5 | — | — |
| Carrots | — | — | Apr 17 – May 15 | Jul 10 – Jul 24 |
| Beets | — | — | Apr 17 – May 15 | Jul 24 – Aug 7 |
| Potatoes | — | — | Apr 17 – May 8 | — |
| Swiss Chard | — | — | Apr 24 – May 22 | Jul 24 – Aug 7 |
| Cilantro | — | — | Apr 24 – May 15 | Aug 7 – Aug 28 |
| Green Beans | — | — | May 15 – Jun 5 | Jul 17 – Jul 31 |
| Sweet Corn | — | — | May 15 – May 29 | — |
| Sweet Potatoes | — | May 22 – Jun 12 | — | — |
| Garlic | — | — | — | Sep 18 – Oct 23 |
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 Ellensburg, WA weather station, 9 km away (elevation 1,480 ft (451 m)).
Frost dates near Kittitas
- Ellensburg May 8 · Oct 2
- Thorp Apr 28 · Oct 7
- Vantage Apr 23 · Oct 12
- Selah May 5 · Oct 4
- Tieton Apr 8 · Oct 23
- Beverly Apr 23 · Oct 12
- Cowiche Apr 8 · Oct 23
- George Apr 21 · Oct 16
- Malaga Apr 8 · Oct 24
- Yakima Apr 8 · Oct 23
Frequently asked questions
When is the last frost in Kittitas, WA?
The median last spring frost in Kittitas, WA is May 8. 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 Kittitas, WA?
The median first fall frost is October 2, with about a 10% chance of frost before September 20.
How long is the growing season in Kittitas, WA?
About 147 days between the median last spring frost and first fall frost.
What planting zone is Kittitas, WA?
Kittitas, WA is in USDA hardiness zone 6b.