Steptoe, WA frost dates
How Steptoe compares
- In 8 years out of 10, the last spring frost in Steptoe falls between April 9 and May 15, a 36-day window. The first fall frost falls between September 19 and October 23.
- The median last frost is 8 days later than the Washington median of Apr 21.
- Its 158-day growing season is longer than 23% of the 491 Washington places with a regular frost season (state median 182 days).
- The last frost is 7 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 123 nights a year at or below 32°F.
- Compared with Spokane, WA, 73 km away, the last frost here is 3 days later than there and the growing season is 14 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 9 |
| 50% (median) | April 29 |
| 10% (safe for tender plants) | May 15 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 19 |
| 50% (median) | October 4 |
| 90% (late) | October 23 |
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 Steptoe, WA
Steptoe, WA frost dates — last frost Apr 29, first frost Oct 4, zone 6b. whenisthelastfrost.com
When to plant vegetables in Steptoe, WA
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 4 – Feb 18 | Apr 1 – Apr 15 | — | — |
| Peppers | Feb 18 – Mar 4 | May 13 – May 27 | — | — |
| Eggplant | Feb 18 – Mar 4 | May 13 – May 27 | — | — |
| Tomatoes | Mar 4 – Mar 18 | May 6 – May 20 | — | — |
| Lettuce | Mar 4 – Mar 18 | Apr 8 – Apr 22 | Apr 1 – May 6 | Aug 9 – Sep 6 |
| Kale | Mar 4 – Mar 18 | Apr 1 – Apr 15 | Apr 1 – Apr 15 | Jul 26 – Aug 16 |
| Broccoli | Mar 4 – Mar 18 | Apr 15 – Apr 29 | — | Jun 28 – Jul 19 |
| Cabbage | Mar 4 – Mar 18 | Apr 8 – Apr 22 | — | Jun 28 – Jul 19 |
| Cauliflower | Mar 4 – Mar 18 | Apr 15 – Apr 29 | — | Jun 28 – Jul 19 |
| Okra | Mar 18 – Apr 1 | May 20 – Jun 3 | May 20 – Jun 3 | — |
| Basil | Mar 18 – Apr 1 | May 6 – May 20 | — | — |
| Peas | — | — | Mar 18 – Apr 8 | Jul 12 – Aug 2 |
| Spinach | — | — | Mar 18 – Apr 8 | Aug 9 – Aug 30 |
| Radishes | — | — | Mar 25 – May 6 | Aug 23 – Sep 13 |
| Cucumbers | Apr 1 – Apr 8 | May 13 – May 20 | May 6 – May 20 | Jul 19 – Aug 2 |
| Zucchini & Summer Squash | Apr 1 – Apr 8 | — | May 6 – May 20 | Jul 26 – Aug 9 |
| Winter Squash & Pumpkins | Apr 1 – Apr 8 | — | May 6 – May 20 | — |
| Melons & Watermelon | Apr 1 – Apr 8 | May 13 – May 27 | — | — |
| Carrots | — | — | Apr 8 – May 6 | Jul 12 – Jul 26 |
| Beets | — | — | Apr 8 – May 6 | Jul 26 – Aug 9 |
| Potatoes | — | — | Apr 8 – Apr 29 | — |
| Swiss Chard | — | — | Apr 15 – May 13 | Jul 26 – Aug 9 |
| Cilantro | — | — | Apr 15 – May 6 | Aug 9 – Aug 30 |
| Green Beans | — | — | May 6 – May 27 | Jul 19 – Aug 2 |
| Sweet Corn | — | — | May 6 – May 20 | — |
| Sweet Potatoes | — | May 13 – Jun 3 | — | — |
| Garlic | — | — | — | Sep 20 – Oct 25 |
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 St John, WA weather station, 20 km away (elevation 1,952 ft (595 m)).
Frost dates near Steptoe
- Thornton May 7 · Sep 28
- Colfax May 6 · Sep 29
- Garfield May 15 · Sep 21
- Belmont May 7 · Sep 28
- Oakesdale May 7 · Sep 28
- Saint John Apr 29 · Oct 4
- Farmington May 15 · Sep 21
- Palouse May 6 · Sep 29
- Rosalia May 7 · Sep 28
- Albion May 6 · Sep 29
Frequently asked questions
When is the last frost in Steptoe, WA?
The median last spring frost in Steptoe, WA is April 29. There is still about a 10% chance of frost after May 15, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Steptoe, WA?
The median first fall frost is October 4, with about a 10% chance of frost before September 19.
How long is the growing season in Steptoe, WA?
About 158 days between the median last spring frost and first fall frost.
What planting zone is Steptoe, WA?
Steptoe, WA is in USDA hardiness zone 6b.