Astoria, OR Frost Dates
Average frost dates, USDA hardiness zone, and growing season length for Astoria, Oregon.
Gardening in Astoria
The Columbia River's mouth city is the wettest, most maritime place in Oregon. Gardening here is PNW cool-season paradise.
Zone 8b with 238 frost-free days. Maritime influence dominates — fog, rain, and mild temperatures year-round. Cool-season crops thrive. Warm-season crops are a stretch.
Astoria's fishing heritage extends to a food culture where growing your own greens to accompany the catch is natural.
What This Means for Astoria Gardeners
The average last spring frost in Astoria is around March 15, and the average first fall frost arrives around November 8. That gives you approximately 238 frost-free days to work with.
That's a generous season. You have time for full-size tomatoes, long-season peppers, and even watermelons without the anxiety of racing the frost. Start warm-season seeds indoors 6-8 weeks before your last frost to hit the ground running. Fall planting is your second opportunity — garlic, kale, lettuce, and broccoli all go in 8-10 weeks before your first frost for harvest into late autumn.
These dates are based on NOAA 30-year Climate Normal data for the Astoria area. Your actual frost dates could shift 2-3 weeks in either direction in any given year. Learn more about our data sources.
What to Grow in Astoria
Astoria's 238-day growing season is generous — long enough for two full growing windows (spring and fall) with warm-season crops between them. You can grow the full range of vegetables, herbs, and flowers with proper timing. Focus on heat-tolerant varieties for midsummer and cool-season crops for extended fall harvests. Recommended starting points: tomatoes, peppers, beans, cucumbers, squash, garlic, kale, and sunflowers.
See the full Oregon planting guide for all 40 plants: Oregon Planting Calendar. Or enter your zip code for exact planting dates personalized to Astoria.
More About Zone 8B
Astoria is in USDA Hardiness Zone 8B, which means average annual extreme minimum temperatures between 15°F to 20°F. View the full Zone 8B planting guide.
See the complete planting calendar for Oregon: Oregon Planting Calendar.
Other Cities in Oregon
Frequently Asked Questions
These dates are based on NOAA's 30-year Climate Normal data for the Astoria area. They represent historical averages, not predictions. In any given year, the actual last frost could be 2-3 weeks earlier or later. Microclimates within Astoria (urban heat islands, hilltops, low-lying valleys) can also shift your local frost dates by a week or more.
Cool-season crops go in 3-4 weeks before your last frost (March 15). Warm-season crops wait until 2 weeks after. You have time for a fall round too — plant cool-season crops again in late summer for harvest into autumn. Enter your zip code for exact dates.