When to plant garlic in zones 3 to 5: one to two weeks after the first frost

Cold-zone extension pages time garlic against the first hard freeze. Wisconsin Extension says planting a week or two after the first killing frost lets roots grow and shoots start inside the clove, without the shoots coming above the soil before the first hard freeze. Minnesota says the same: roots and shoots come out of the clove by the first hard freeze, but the shoots usually stay below ground until spring.

Source: University of Wisconsin Extension, Garlic (A3785), checked October 9, 2026; University of Minnesota Extension, Growing garlic in home gardens, checked October 8, 2026.

Maine's bulletin puts the risk plainly. Plant too early and the top comes up above the soil, where winter can injure it. That's the reverse of zones 6 to 7, where extension pages plant around the first frost. In these states you wait for it.

Source: University of Maine Extension, Bulletin #2063 Growing Hardneck Garlic in Your Maine Garden, checked October 9, 2026.

Frost dates are NOAA 1991 to 2020 normals for the station nearest each zip code (32°F). The planting column adds 7 and 14 days to the typical date.

Source: University of Minnesota Extension, Growing garlic in home gardens, checked October 8, 2026; University of Wisconsin Extension, Garlic (A3785), checked October 9, 2026; NOAA 1991-2020 U.S. Climate Normals, annual/seasonal, checked October 7, 2026; NOAA 1991-2020 annual/seasonal normals documentation, checked October 7, 2026; PRISM 2023 USDA hardiness zone GIS datasets and zip-code listing, checked October 6, 2026.

• 1 to 2 weeksafter the first killing frost (Minnesota, Wisconsin)University of Minnesota Extension, Growing garlic in home gardens, October 8, 2026
• Sep 26typical first fall frost, Cass Lake station near BemidjiNOAA 1991-2020 U.S. Climate Normals, annual/seasonal, October 7, 2026
• Mid-Sep to OctMaine's window, north to southUniversity of Maine Extension, Bulletin #2063 Growing Hardneck Garlic in Your Maine Garden, October 9, 2026
• 3 to 4 inof straw or leaves over the bed after plantingUniversity of Minnesota Extension, Growing garlic in home gardens, October 8, 2026

1. 1

   Look up your first fall frost

   Type your zip code into the frost date lookup. Write down the typical first fall frost and the 1 in 10 earlier date.

   Source: NOAA 1991-2020 U.S. Climate Normals, annual/seasonal, checked October 7, 2026.

2. 2

   Add one to two weeks

   Count 7 and 14 days from the typical date. That span is your planting week. Our lookup gives the 32°F date; neither Minnesota nor Wisconsin gives a temperature for a killing frost, so we use the typical 32°F date as the marker.

   Source: University of Minnesota Extension, Growing garlic in home gardens, checked October 8, 2026; University of Wisconsin Extension, Garlic (A3785), checked October 9, 2026.

3. 3

   Watch the real first frost

   The date in the table is a 30-year normal. If your first frost comes early this year, the planting week moves up with it; if it comes late, wait for it.

   Source: NOAA 1991-2020 U.S. Climate Normals, annual/seasonal, checked October 7, 2026.

4. 4

   Count the cloves

   Use the garlic calculator for the clove count. Minnesota and Wisconsin both plant cloves pointed side up, 2 to 3 inches deep and about 6 inches apart.

   Source: University of Minnesota Extension, Growing garlic in home gardens, checked October 8, 2026; University of Wisconsin Extension, Garlic (A3785), checked October 9, 2026.

5. 5

   Mulch the same week

   Cover the bed with 3 to 4 inches of straw or shredded leaves once the cloves are in.

   Source: University of Minnesota Extension, Growing garlic in home gardens, checked October 8, 2026; University of Wisconsin Extension, Garlic (A3785), checked October 9, 2026.

Maine's bulletin skips the frost rule and gives a calendar span: about mid-September in the north to the end of October in the south. Presque Isle, in zone 4a, has a typical first fall frost of September 26, near the early end of that span. Iowa State says October to early November.

Source: University of Maine Extension, Bulletin #2063 Growing Hardneck Garlic in Your Maine Garden, checked October 9, 2026; Iowa State Extension, When should I plant garlic?, checked October 8, 2026; NOAA 1991-2020 U.S. Climate Normals, annual/seasonal, checked October 7, 2026; PRISM 2023 USDA hardiness zone GIS datasets and zip-code listing, checked October 6, 2026.

If your state's extension service gives its own window, go by it. The frost rule is the tiebreaker when the window is wide.

Source: University of Minnesota Extension, Growing garlic in home gardens, checked October 8, 2026.