Timber, OR frost dates
How Timber compares
- In 8 years out of 10, the last spring frost in Timber falls between April 18 and May 29, a 41-day window. The first fall frost falls between September 11 and October 28.
- The median last frost is 22 days later than the Oregon median of Apr 16.
- Its 146-day growing season is longer than 22% of the 345 Oregon places with a regular frost season (state median 193 days).
- The last frost is 53 days later than the zone 8b median of Mar 16. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 8b chart.
- The weather station records an average of 99 nights a year at or below 32°F.
- Compared with Hillsboro, OR, 35 km away, the last frost here is 22 days later than there and the growing season is 44 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 18 |
| 50% (median) | May 8 |
| 10% (safe for tender plants) | May 29 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 11 |
| 50% (median) | October 1 |
| 90% (late) | October 28 |
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 Timber, OR
Timber, OR frost dates — last frost May 8, first frost Oct 1, zone 8b. whenisthelastfrost.com
When to plant vegetables in Timber, OR
| 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 6 – Sep 3 |
| Kale | Mar 13 – Mar 27 | Apr 10 – Apr 24 | Apr 10 – Apr 24 | Jul 23 – Aug 13 |
| Broccoli | Mar 13 – Mar 27 | Apr 24 – May 8 | — | Jun 25 – Jul 16 |
| Cabbage | Mar 13 – Mar 27 | Apr 17 – May 1 | — | Jun 25 – Jul 16 |
| Cauliflower | Mar 13 – Mar 27 | Apr 24 – May 8 | — | Jun 25 – Jul 16 |
| 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 9 – Jul 30 |
| Spinach | — | — | Mar 27 – Apr 17 | Aug 6 – Aug 27 |
| Radishes | — | — | Apr 3 – May 15 | Aug 20 – Sep 10 |
| Cucumbers | Apr 10 – Apr 17 | May 22 – May 29 | May 15 – May 29 | Jul 16 – Jul 30 |
| Zucchini & Summer Squash | Apr 10 – Apr 17 | — | May 15 – May 29 | Jul 23 – Aug 6 |
| 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 9 – Jul 23 |
| Beets | — | — | Apr 17 – May 15 | Jul 23 – Aug 6 |
| Potatoes | — | — | Apr 17 – May 8 | — |
| Swiss Chard | — | — | Apr 24 – May 22 | Jul 23 – Aug 6 |
| Cilantro | — | — | Apr 24 – May 15 | Aug 6 – Aug 27 |
| Green Beans | — | — | May 15 – Jun 5 | Jul 16 – Jul 30 |
| Sweet Corn | — | — | May 15 – May 29 | — |
| Sweet Potatoes | — | May 22 – Jun 12 | — | — |
| Garlic | — | — | — | Sep 17 – Oct 22 |
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 Vernonia #2, OR weather station, 18 km away (elevation 627 ft (191 m)).
Frost dates near Timber
- Buxton May 8 · Oct 1
- Manning Apr 16 · Oct 26
- Gales Creek Apr 16 · Oct 26
- Banks Apr 16 · Oct 26
- Vernonia May 8 · Oct 1
- Forest Grove Apr 16 · Oct 26
- North Plains Apr 16 · Oct 23
- Cornelius Apr 16 · Oct 26
- Scappoose Apr 10 · Nov 2
- Gaston Apr 16 · Oct 26
Frequently asked questions
When is the last frost in Timber, OR?
The median last spring frost in Timber, OR is May 8. There is still about a 10% chance of frost after May 29, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Timber, OR?
The median first fall frost is October 1, with about a 10% chance of frost before September 11.
How long is the growing season in Timber, OR?
About 146 days between the median last spring frost and first fall frost.
What planting zone is Timber, OR?
Timber, OR is in USDA hardiness zone 8b.