blissgarden.

When to plant onion in Alaska

Alaska spans USDA zones 2a–6a, so the right time to plant onion shifts by weeks across the state. The window to transplant seedlings outdoors runs from about April 5 in Juneau city and to April 24 in Badger — below are local dates for 7 cities, each computed from its own frost dates.

In Anchoragethe onion transplant out window (April 18–May 2) has passed for this year.
CityZoneLast frostFirst frostTransplant out
Anchorage5aMay 16September 20April 18 – May 2
Fairbanks2aMay 16September 6April 18 – May 2
Juneau city and6aMay 3October 14April 5 – April 19
Knik-Fairview5aMay 18September 20April 20 – May 4
Badger2aMay 22September 2April 24 – May 8
College2bMay 18September 6April 20 – May 4
North Lakes5aMay 16September 23April 18 – May 2

Onion in Alaska: FAQ

When can I plant onion in Alaska?

Across Alaska, the time to transplant onion spans roughly April 5 in Juneau city and to April 24 in Badger, each following that city's local frost dates.

Does the onion planting date vary across Alaska?

Yes. Alaska publishes 7 cities with their own frost dates, so the right onion planting window shifts by weeks between the warmest and coldest parts of the state — use your city's page for the exact dates.

How long does onion take to grow in Alaska?

Onion takes about 90–110 days to reach harvest once planted — check that this fits inside your city's frost-free season on its place page.

Planting reminders

Never miss a window in your area

An email when it’s time to start seeds, transplant, and sow — timed to your frost dates. Double opt-in, one-click unsubscribe, no spam.

Onion planting guide →All Alaska cities →Alaska planting calendar →