Fairbanks, AK Frost Dates
Average frost dates, USDA hardiness zone, and growing season length for Fairbanks, Alaska.
Gardening in Fairbanks
Interior Alaska's largest city is the most extreme gardening environment in this guide — and Fairbanks gardeners embrace it with a determination that borders on heroism.
Zone 3a with only 103 frost-free days and winter temperatures that reach -40°F. But here's the miracle: nearly 24 hours of sunlight in June and July produce growth rates that seem impossible. The summer sun literally never sets, and plants photosynthesize around the clock. Those 100-pound Alaska State Fair cabbages? Many start in Fairbanks.
The Tanana Valley State Fair celebrates interior Alaska's improbable growing season. Permafrost complicates in-ground gardening, so raised beds and high tunnels are standard equipment. Fairbanks gardeners are the most resourceful in America — they have to be.
What This Means for Fairbanks Gardeners
The average last spring frost in Fairbanks is around May 25, and the average first fall frost arrives around September 5. That gives you approximately 103 frost-free days to work with.
103 frost-free days means every warm day counts. Focus on cold-hardy crops that thrive in your moderate temperatures: kale, lettuce, peas, radishes, potatoes, and root vegetables. For warm-season crops, choose only the shortest-season varieties (sub-65-day tomatoes, 55-day beans) and start everything indoors. Season extension — row covers, cold frames, plastic mulch — isn't a luxury here, it's essential infrastructure.
These dates are based on NOAA 30-year Climate Normal data for the Fairbanks 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 Fairbanks
With 103 frost-free days, Fairbanks gardeners need to plan strategically — start warm-season crops indoors and choose short-season varieties. Cool-season crops are your strength, thriving in the moderate temperatures that define your growing window. Recommended starting points: kale, lettuce, peas, carrots, potatoes, radishes, garlic, and short-season tomatoes.
See the full Alaska planting guide for all 40 plants: Alaska Planting Calendar. Or enter your zip code for exact planting dates personalized to Fairbanks.
More About Zone 3A
Fairbanks is in USDA Hardiness Zone 3A, which means average annual extreme minimum temperatures between -40°F to -35°F. View the full Zone 3A planting guide.
See the complete planting calendar for Alaska: Alaska Planting Calendar.
Other Cities in Alaska
Frequently Asked Questions
These dates are based on NOAA's 30-year Climate Normal data for the Fairbanks 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 Fairbanks (urban heat islands, hilltops, low-lying valleys) can also shift your local frost dates by a week or more.
Start everything possible indoors — your 103-day season doesn't leave room for a slow start. Direct sow only the fastest, hardiest crops (radishes, lettuce, peas) 3-4 weeks before last frost (May 25). Choose short-season varieties for warm crops. Enter your zip code for exact dates.