Saint John, WA frost dates
Last spring frostApr 29median date
First fall frostOct 4median date
Growing season158 daysfrost-free
Hardiness zone6bZone 6b
How Saint John compares
- In 8 years out of 10, the last spring frost in Saint John 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, 67 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 Saint John, WA
Saint John, WA frost dates — last frost Apr 29, first frost Oct 4, zone 6b. whenisthelastfrost.com
Crop
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Start indoors: Feb 4 to Feb 18Transplant outside: Apr 1 to Apr 15
Start indoors: Feb 18 to Mar 4Transplant outside: May 13 to May 27
Start indoors: Feb 18 to Mar 4Transplant outside: May 13 to May 27
Start indoors: Mar 4 to Mar 18Transplant outside: May 6 to May 20
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 8 to Apr 22Sow outdoors: Apr 1 to May 6Plant for fall: Aug 9 to Sep 6
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 1 to Apr 15Sow outdoors: Apr 1 to Apr 15Plant for fall: Jul 26 to Aug 16
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 15 to Apr 29Plant for fall: Jun 28 to Jul 19
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 8 to Apr 22Plant for fall: Jun 28 to Jul 19
Start indoors: Mar 4 to Mar 18Transplant outside: Apr 15 to Apr 29Plant for fall: Jun 28 to Jul 19
Start indoors: Mar 18 to Apr 1Transplant outside: May 20 to Jun 3Sow outdoors: May 20 to Jun 3
Start indoors: Mar 18 to Apr 1Transplant outside: May 6 to May 20
Sow outdoors: Mar 18 to Apr 8Plant for fall: Jul 12 to Aug 2
Sow outdoors: Mar 18 to Apr 8Plant for fall: Aug 9 to Aug 30
Sow outdoors: Mar 25 to May 6Plant for fall: Aug 23 to Sep 13
Start indoors: Apr 1 to Apr 8Transplant outside: May 13 to May 20Sow outdoors: May 6 to May 20Plant for fall: Jul 19 to Aug 2
Start indoors: Apr 1 to Apr 8Sow outdoors: May 6 to May 20Plant for fall: Jul 26 to Aug 9
Start indoors: Apr 1 to Apr 8Sow outdoors: May 6 to May 20
Start indoors: Apr 1 to Apr 8Transplant outside: May 13 to May 27
Sow outdoors: Apr 8 to May 6Plant for fall: Jul 12 to Jul 26
Sow outdoors: Apr 8 to May 6Plant for fall: Jul 26 to Aug 9
Sow outdoors: Apr 8 to Apr 29
Sow outdoors: Apr 15 to May 13Plant for fall: Jul 26 to Aug 9
Sow outdoors: Apr 15 to May 6Plant for fall: Aug 9 to Aug 30
Sow outdoors: May 6 to May 27Plant for fall: Jul 19 to Aug 2
Sow outdoors: May 6 to May 20
Transplant outside: May 13 to Jun 3
Plant for fall: Sep 20 to Oct 25
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Saint John, 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, 2 km away (elevation 1,952 ft (595 m)).
Frost dates near Saint John
- Thornton May 7 · Sep 28
- Steptoe Apr 29 · Oct 4
- Malden May 7 · Sep 28
- Endicott May 13 · Sep 26
- Rosalia May 7 · Sep 28
- Oakesdale May 7 · Sep 28
- Lamont Apr 29 · Oct 4
- Colfax May 6 · Sep 29
- Belmont May 7 · Sep 28
- Garfield May 15 · Sep 21
Frequently asked questions
When is the last frost in Saint John, WA?
The median last spring frost in Saint John, 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 Saint John, 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 Saint John, WA?
About 158 days between the median last spring frost and first fall frost.
What planting zone is Saint John, WA?
Saint John, WA is in USDA hardiness zone 6b.