When to plant garlic in Alaska
Alaska’s average last spring frost is May 17, and the first fall frost typically arrives around September 13 — about 119 frost-free days (USDA zones 1a, 2b, 3b, 4b, 5b, 6b, 7b, 8b). Garlic needs 240–270 days to mature, which is tight for a full-season planting there — see the note below.
Alaska covers a wide range of climates, so your exact frost dates may differ from the state average by two weeks or more. For dates tuned to your town, use the calendar generator.
When to plant garlic in Alaska: the short answer
For a spring planting, sow Sep 24 – Oct 11. Seeds germinate in soil from 32 to 75°F.
Windows are ~1–2 week bands around each date. Frost dates are a statewide average from NOAA/NCEI normals; your town may differ by two weeks or more. Calendar year 2026.
How to grow garlic in Alaska, step by step
- Prepare the bed. It needs at least six to eight hours of direct sun a day and loose soil at least 12 inches deep, with a pH between 5.5 and 7.5. Dig in compost before planting.
- Water and feed. Give it steady, even moisture, about an inch of water a week from rain or the hose.
- Watch for pests and problems. Pests: onion maggot, onion thrips, stem nematode. Diseases and disorders: white rot, rust, basal rot.
- Harvest. Garlic takes 240-270 days to reach harvest. Plant cloves 2-4 weeks after the first fall frost, pointy end up, and mulch. Hardneck types need this cold period; softneck types suit mild-winter regions and braid well. Harvest the following summer when the lower leaves brown.
Figures come from our crop data; dates use Alaska’s average frost dates. More in the full garlic growing guide.
Garlic planting dates by USDA zone in Alaska
Alaska spans USDA zones 1a, 2b, 3b, 4b, 5b, 6b, 7b, 8b. Colder zones, usually higher or further inland, have a later last spring frost and an earlier first fall frost than the state average, so the garlic dates shift with them.
| Zone | Last frost | First frost | Season | Start indoors | Plant garlic |
|---|---|---|---|---|---|
| Zone 1 | Jun 15 | Aug 20 | 65 days | - | Aug 31 – Sep 17 |
| Zone 2 | Jun 1 | Sep 1 | 90 days | - | Sep 12 – Sep 29 |
| Zone 3 | May 15 | Sep 15 | 120 days | - | Sep 26 – Oct 13 |
| Zone 4 | May 10 | Sep 25 | 135 days | - | Oct 6 – Oct 23 |
| Zone 5 | Apr 30 | Oct 5 | 160 days | - | Oct 16 – Nov 2 |
| Zone 6 | Apr 15 | Oct 15 | 185 days | - | Oct 26 – Nov 12 |
| Zone 7 | Apr 5 | Oct 25 | 200 days | - | Nov 5 – Nov 22 |
| Zone 8 | Mar 20 | Nov 5 | 230 days | - | Nov 16 – Dec 3 |
When to plant garlic in nearby states
| State | Last frost | Plant in fall |
|---|---|---|
| Alaska (this page) | May 17 | Sep 24 – Oct 11 |
| Hawaii | frost-free | - |
Questions gardeners in Alaska ask
When is the best time to plant garlic in Alaska?
Plant garlic in Alaska between September 24 and October 11. That timing is set for fall, after Alaska's first frost (about September 13); Alaska spans several climates, so cooler and higher parts of the state run later.
When will fall-planted garlic be ready in Alaska?
The following May to June. Garlic roots in fall, rests over winter and finishes in early summer - harvest when the lower leaves turn brown.
When is the last frost in Alaska?
On average around May 17, with the first fall frost around September 13 - about 119 frost-free days. Your town may differ by two weeks or more.