Heppner, OR frost dates
Last spring frostApr 26median date
First fall frostOct 19median date
Growing season176 daysfrost-free
Hardiness zone7aZone 7a
How Heppner compares
- In 8 years out of 10, the last spring frost in Heppner falls between April 6 and May 11, a 35-day window. The first fall frost falls between October 3 and November 2.
- The median last frost is 10 days later than the Oregon median of Apr 16.
- Its 176-day growing season is longer than 39% of the 345 Oregon places with a regular frost season (state median 193 days).
- The last frost is 10 days later 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 106 nights a year at or below 32°F.
- Compared with Kennewick, WA, 97 km away, the last frost here is 29 days later than there and the growing season is 40 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 6 |
| 50% (median) | April 26 |
| 10% (safe for tender plants) | May 11 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | October 3 |
| 50% (median) | October 19 |
| 90% (late) | November 2 |
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 Heppner, OR
Heppner, OR frost dates — last frost Apr 26, first frost Oct 19, zone 7a. whenisthelastfrost.com
Crop
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Start indoors: Feb 1 to Feb 15Transplant outside: Mar 29 to Apr 12
Start indoors: Feb 15 to Mar 1Transplant outside: May 10 to May 24
Start indoors: Feb 15 to Mar 1Transplant outside: May 10 to May 24
Start indoors: Mar 1 to Mar 15Transplant outside: May 3 to May 17
Start indoors: Mar 1 to Mar 15Transplant outside: Apr 5 to Apr 19Sow outdoors: Mar 29 to May 3Plant for fall: Aug 24 to Sep 21
Start indoors: Mar 1 to Mar 15Transplant outside: Mar 29 to Apr 12Sow outdoors: Mar 29 to Apr 12Plant for fall: Aug 10 to Aug 31
Start indoors: Mar 1 to Mar 15Transplant outside: Apr 12 to Apr 26Plant for fall: Jul 13 to Aug 3
Start indoors: Mar 1 to Mar 15Transplant outside: Apr 5 to Apr 19Plant for fall: Jul 13 to Aug 3
Start indoors: Mar 1 to Mar 15Transplant outside: Apr 12 to Apr 26Plant for fall: Jul 13 to Aug 3
Start indoors: Mar 15 to Mar 29Transplant outside: May 17 to May 31Sow outdoors: May 17 to May 31
Start indoors: Mar 15 to Mar 29Transplant outside: May 3 to May 17
Sow outdoors: Mar 15 to Apr 5Plant for fall: Jul 27 to Aug 17
Sow outdoors: Mar 15 to Apr 5Plant for fall: Aug 24 to Sep 14
Sow outdoors: Mar 22 to May 3Plant for fall: Sep 7 to Sep 28
Start indoors: Mar 29 to Apr 5Transplant outside: May 10 to May 17Sow outdoors: May 3 to May 17Plant for fall: Aug 3 to Aug 17
Start indoors: Mar 29 to Apr 5Sow outdoors: May 3 to May 17Plant for fall: Aug 10 to Aug 24
Start indoors: Mar 29 to Apr 5Sow outdoors: May 3 to May 17
Start indoors: Mar 29 to Apr 5Transplant outside: May 10 to May 24
Sow outdoors: Apr 5 to May 3Plant for fall: Jul 27 to Aug 10
Sow outdoors: Apr 5 to May 3Plant for fall: Aug 10 to Aug 24
Sow outdoors: Apr 5 to Apr 26
Sow outdoors: Apr 12 to May 10Plant for fall: Aug 10 to Aug 24
Sow outdoors: Apr 12 to May 3Plant for fall: Aug 24 to Sep 14
Sow outdoors: May 3 to May 24Plant for fall: Aug 3 to Aug 17
Sow outdoors: May 3 to May 17
Transplant outside: May 10 to May 31
Plant for fall: Oct 5 to Nov 9
Start indoorsTransplant outsideSow outdoorsPlant for fallMedian frost dates
When to plant vegetables in Heppner, OR
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 1 – Feb 15 | Mar 29 – Apr 12 | — | — |
| Peppers | Feb 15 – Mar 1 | May 10 – May 24 | — | — |
| Eggplant | Feb 15 – Mar 1 | May 10 – May 24 | — | — |
| Tomatoes | Mar 1 – Mar 15 | May 3 – May 17 | — | — |
| Lettuce | Mar 1 – Mar 15 | Apr 5 – Apr 19 | Mar 29 – May 3 | Aug 24 – Sep 21 |
| Kale | Mar 1 – Mar 15 | Mar 29 – Apr 12 | Mar 29 – Apr 12 | Aug 10 – Aug 31 |
| Broccoli | Mar 1 – Mar 15 | Apr 12 – Apr 26 | — | Jul 13 – Aug 3 |
| Cabbage | Mar 1 – Mar 15 | Apr 5 – Apr 19 | — | Jul 13 – Aug 3 |
| Cauliflower | Mar 1 – Mar 15 | Apr 12 – Apr 26 | — | Jul 13 – Aug 3 |
| Okra | Mar 15 – Mar 29 | May 17 – May 31 | May 17 – May 31 | — |
| Basil | Mar 15 – Mar 29 | May 3 – May 17 | — | — |
| Peas | — | — | Mar 15 – Apr 5 | Jul 27 – Aug 17 |
| Spinach | — | — | Mar 15 – Apr 5 | Aug 24 – Sep 14 |
| Radishes | — | — | Mar 22 – May 3 | Sep 7 – Sep 28 |
| Cucumbers | Mar 29 – Apr 5 | May 10 – May 17 | May 3 – May 17 | Aug 3 – Aug 17 |
| Zucchini & Summer Squash | Mar 29 – Apr 5 | — | May 3 – May 17 | Aug 10 – Aug 24 |
| Winter Squash & Pumpkins | Mar 29 – Apr 5 | — | May 3 – May 17 | — |
| Melons & Watermelon | Mar 29 – Apr 5 | May 10 – May 24 | — | — |
| Carrots | — | — | Apr 5 – May 3 | Jul 27 – Aug 10 |
| Beets | — | — | Apr 5 – May 3 | Aug 10 – Aug 24 |
| Potatoes | — | — | Apr 5 – Apr 26 | — |
| Swiss Chard | — | — | Apr 12 – May 10 | Aug 10 – Aug 24 |
| Cilantro | — | — | Apr 12 – May 3 | Aug 24 – Sep 14 |
| Green Beans | — | — | May 3 – May 24 | Aug 3 – Aug 17 |
| Sweet Corn | — | — | May 3 – May 17 | — |
| Sweet Potatoes | — | May 10 – May 31 | — | — |
| Garlic | — | — | — | Oct 5 – Nov 9 |
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 Heppner, OR weather station, 3 km away (elevation 1,886 ft (575 m)).
Frost dates near Heppner
- Lexington Apr 26 · Oct 19
- Ione Apr 26 · Oct 19
- Echo Apr 26 · Oct 10
- Condon May 10 · Oct 7
- Mikkalo May 10 · Oct 7
- Pilot Rock May 7 · Oct 4
- Stanfield Apr 26 · Oct 10
- Boardman Apr 14 · Oct 21
- Ukiah May 7 · Oct 4
- Hermiston Apr 27 · Oct 7
Frequently asked questions
When is the last frost in Heppner, OR?
The median last spring frost in Heppner, OR is April 26. There is still about a 10% chance of frost after May 11, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Heppner, OR?
The median first fall frost is October 19, with about a 10% chance of frost before October 3.
How long is the growing season in Heppner, OR?
About 176 days between the median last spring frost and first fall frost.
What planting zone is Heppner, OR?
Heppner, OR is in USDA hardiness zone 7a.