Monument, OR frost dates
How Monument compares
- In 8 years out of 10, the last spring frost in Monument falls between April 25 and May 26, a 31-day window. The first fall frost falls between September 9 and October 10.
- The median last frost is 23 days later than the Oregon median of Apr 16.
- Its 141-day growing season is longer than 20% of the 345 Oregon places with a regular frost season (state median 193 days).
- The last frost is 23 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 158 nights a year at or below 32°F.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 25 |
| 50% (median) | May 9 |
| 10% (safe for tender plants) | May 26 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 9 |
| 50% (median) | September 27 |
| 90% (late) | October 10 |
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 Monument, OR
Monument, OR frost dates — last frost May 9, first frost Sep 27, zone 7a. whenisthelastfrost.com
When to plant vegetables in Monument, OR
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Feb 14 – Feb 28 | Apr 11 – Apr 25 | — | — |
| Peppers | Feb 28 – Mar 14 | May 23 – Jun 6 | — | — |
| Eggplant | Feb 28 – Mar 14 | May 23 – Jun 6 | — | — |
| Tomatoes | Mar 14 – Mar 28 | May 16 – May 30 | — | — |
| Lettuce | Mar 14 – Mar 28 | Apr 18 – May 2 | Apr 11 – May 16 | Aug 2 – Aug 30 |
| Kale | Mar 14 – Mar 28 | Apr 11 – Apr 25 | Apr 11 – Apr 25 | Jul 19 – Aug 9 |
| Broccoli | Mar 14 – Mar 28 | Apr 25 – May 9 | — | Jun 21 – Jul 12 |
| Cabbage | Mar 14 – Mar 28 | Apr 18 – May 2 | — | Jun 21 – Jul 12 |
| Cauliflower | Mar 14 – Mar 28 | Apr 25 – May 9 | — | Jun 21 – Jul 12 |
| Okra | Mar 28 – Apr 11 | May 30 – Jun 13 | May 30 – Jun 13 | — |
| Basil | Mar 28 – Apr 11 | May 16 – May 30 | — | — |
| Peas | — | — | Mar 28 – Apr 18 | Jul 5 – Jul 26 |
| Spinach | — | — | Mar 28 – Apr 18 | Aug 2 – Aug 23 |
| Radishes | — | — | Apr 4 – May 16 | Aug 16 – Sep 6 |
| Cucumbers | Apr 11 – Apr 18 | May 23 – May 30 | May 16 – May 30 | Jul 12 – Jul 26 |
| Zucchini & Summer Squash | Apr 11 – Apr 18 | — | May 16 – May 30 | Jul 19 – Aug 2 |
| Winter Squash & Pumpkins | Apr 11 – Apr 18 | — | May 16 – May 30 | — |
| Melons & Watermelon | Apr 11 – Apr 18 | May 23 – Jun 6 | — | — |
| Carrots | — | — | Apr 18 – May 16 | Jul 5 – Jul 19 |
| Beets | — | — | Apr 18 – May 16 | Jul 19 – Aug 2 |
| Potatoes | — | — | Apr 18 – May 9 | — |
| Swiss Chard | — | — | Apr 25 – May 23 | Jul 19 – Aug 2 |
| Cilantro | — | — | Apr 25 – May 16 | Aug 2 – Aug 23 |
| Green Beans | — | — | May 16 – Jun 6 | Jul 12 – Jul 26 |
| Sweet Corn | — | — | May 16 – May 30 | — |
| Sweet Potatoes | — | May 23 – Jun 13 | — | — |
| Garlic | — | — | — | Sep 13 – Oct 18 |
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 Monument, OR weather station, about 1 km away (elevation 1,995 ft (608 m)).
Frost dates near Monument
- Kimberly May 9 · Sep 27
- Long Creek Jun 5 · Sep 14
- Spray May 9 · Sep 27
- Dayville May 4 · Oct 6
- Ukiah May 7 · Oct 4
- Mount Vernon May 28 · Sep 18
- Fossil Jun 3 · Sep 14
- John Day May 28 · Sep 18
- Heppner Apr 26 · Oct 19
- Canyon City May 28 · Sep 18
Frequently asked questions
When is the last frost in Monument, OR?
The median last spring frost in Monument, OR is May 9. There is still about a 10% chance of frost after May 26, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Monument, OR?
The median first fall frost is September 27, with about a 10% chance of frost before September 9.
How long is the growing season in Monument, OR?
About 141 days between the median last spring frost and first fall frost.
What planting zone is Monument, OR?
Monument, OR is in USDA hardiness zone 7a.