Juneau, AK Frost Dates
Average frost dates, USDA hardiness zone, and growing season length for Juneau, Alaska.
Gardening in Juneau
Alaska's capital is accessible only by air or sea, giving Juneau's food gardens strategic importance beyond hobby. Growing food here is about resilience as much as recreation.
Zone 7a seems warm for Alaska, but it's the maritime influence — the Inside Passage keeps temperatures moderate but delivers 60+ inches of rain annually. Your 173-day growing season is surprisingly long for Alaska. The challenge is sunlight — Juneau's mountain surroundings and overcast skies limit the solar energy that drives growth.
Juneau's isolation from the road system makes food self-sufficiency meaningful. The Juneau Community Garden and the Southeast Alaska Master Gardeners help residents grow food in conditions that are unique even by Alaska standards.
What This Means for Juneau Gardeners
The average last spring frost in Juneau is around April 20, and the average first fall frost arrives around October 10. That gives you approximately 173 frost-free days to work with.
A solid, workable season. Most standard vegetable varieties have enough time to mature, though the longest-season crops (like sweet potatoes at 90+ days or large watermelons at 85+ days) need to be started early and chosen carefully. Indoor seed starting isn't optional — it's how you buy the extra weeks that make the difference between a good harvest and a great one.
These dates are based on NOAA 30-year Climate Normal data for the Juneau 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 Juneau
Juneau's 173-day season gives you plenty of time for most vegetables with good planning. Start warm-season crops indoors to maximize your window. Cool-season crops thrive in your spring and fall shoulder seasons. Recommended starting points: tomatoes, peppers, lettuce, carrots, beans, broccoli, garlic, and basil.
See the full Alaska planting guide for all 40 plants: Alaska Planting Calendar. Or enter your zip code for exact planting dates personalized to Juneau.
More About Zone 7A
Juneau is in USDA Hardiness Zone 7A, which means average annual extreme minimum temperatures between 0°F to 5°F. View the full Zone 7A 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 Juneau 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 Juneau (urban heat islands, hilltops, low-lying valleys) can also shift your local frost dates by a week or more.
Start warm-season seeds indoors 6-8 weeks before your last frost (April 20) to maximize your 173-day window. Direct sow cold-hardy crops like peas and lettuce 3-4 weeks before last frost. Every week of early indoor starting matters at this season length. Enter your zip code for exact dates.