Oregon Planting Guide & Growing Season
Oregon is in USDA hardiness zone 5b-9b with a growing season of 190 days. The average last spring frost is Apr 15 and the average first fall frost is Oct 20.
Growing Conditions in Oregon
How Oregon Compares
Compare Oregon's growing conditions with states that have similar climates.
| State | USDA Zone | Last Frost | First Frost | Season (days) |
|---|---|---|---|---|
| Oregon (OR) | 5b-9b | Apr 15 | Oct 20 | 190 |
| Alabama (AL) | 7a-8b | Mar 15 | Nov 5 | 235 |
| Alaska (AK) | 1a-7b | May 30 | Sep 5 | 100 |
| Arizona (AZ) | 4b-10b | Mar 1 | Nov 15 | 260 |
| Arkansas (AR) | 6b-8a | Apr 1 | Oct 25 | 210 |
| California (CA) | 4b-11a | Feb 15 | Nov 30 | 290 |
Frequently Asked Questions About Gardening in Oregon
When should I start seeds indoors in Oregon?
In Oregon, the average last frost date is Apr 15. Start most seeds indoors 6-8 weeks before this date. The USDA hardiness zone for Oregon is 5b-9b, with a growing season of approximately 190 days.
What USDA hardiness zone is Oregon?
Oregon falls in USDA hardiness zones 5b-9b. This affects which perennial plants will survive winter and influences optimal planting times.
When is the first frost in Oregon?
The average first frost date in Oregon is Oct 20. Plan to harvest cold-sensitive crops before this date or protect them with row covers.
How long is the growing season in Oregon?
Oregon has an average growing season of 190 days, from the last frost (Apr 15) to first frost (Oct 20). This moderate season works well for most common vegetables.
Plan Your Garden
Use our seed starting calculator to get personalized planting dates, or browse all states.