Minnesota planting calendar

When to plant garlic in Minnesota — sow, transplant & harvest dates

Minnesota is mostly USDA zone 4b (range 3a-5a). Dates below are derived from garlic's frost tolerance and Minnesota's frost window — not generic national averages.

Garlic planting timetable for Minnesota

Stage	When in Minnesota	Anchor
Plant cloves outdoors	mid-August — late August (August 21)	~35 days before Minnesota's first fall frost (late September)
First harvest	late April the following year	~240 days from autumn planting

Dates are state-wide averages for the dominant zone. Local microclimates — elevation, urban heat, coastal moderation — can shift the window by 1-2 weeks. Use the frost-date calculator for a date tuned to your town.

Why Minnesota's climate shifts the garlic dates

Minnesota's first fall frost averages late September, which sets the autumn planting clock — cloves need 4-6 weeks of root growth before the ground freezes. Minnesota is one of the coldest states in the contiguous US. Cold-hardy varieties and a compressed season define gardening here.

Garlic is the unusual one — plant cloves in autumn (4-6 weeks before the first hard fall frost) so they put down roots before winter, then break dormancy in spring and bulb up over the long days of early summer. Cold-winter zones grow hardneck varieties; mild-winter zones do better with softneck.

Frost-risk note

Get cloves in before the ground freezes solid; in the far north near International Falls (zone 3a) mulch heavily with 10-15 cm of straw to stop freeze-thaw heaving.

Regional variation within Minnesota

the far north near International Falls (zone 3a) should plant at the earlier end of the window and grow hardneck types; the Twin Cities metro and far south (zone 5a) can plant later and lean on softneck varieties.

Minneapolis — USDA zone 5a
Saint Paul — USDA zone 5a
Duluth — USDA zone 4b
Rochester — USDA zone 4b

What else to plant in Minnesota around then

The same autumn slot suits overwintering onions, shallots, and a final sowing of spinach or mache.

Quick-grow guide

Sun: Full sun — 6+ hours direct.
Soil temperature for germination: Soil 10-15 °C (50-60 °F) at planting.
Spacing: 4-6 inches (10-15 cm) between plants.
Days to harvest: ~240 days from autumn planting.

Frequently asked questions

When is the best time to plant garlic in Minnesota?

In Minnesota (mostly USDA zone 4b), plant garlic cloves outdoors around mid-August — late August — roughly 35 days before the first fall frost (late September). Cloves root through autumn, overwinter, then bulb up by late April next year. Garlic is fall-planted — cloves need winter chilling, so they go in the ground in autumn, root before the freeze, and bulb up the following summer.

What USDA zone is Minnesota?

Most of Minnesota sits in USDA hardiness zone 4b, with the state spanning roughly 3a-5a from the far north near International Falls (zone 3a) to the Twin Cities metro and far south (zone 5a). The last spring frost averages mid-May and the first fall frost late September.

Can you grow garlic in Minnesota?

Yes. Minnesota's dominant zone 4b supports garlic — the key is timing. Garlic is fall-planted — cloves need winter chilling, so they go in the ground in autumn, root before the freeze, and bulb up the following summer.

Does the planting date change across Minnesota?

What else can I plant in Minnesota around the same time?

The same autumn slot suits overwintering onions, shallots, and a final sowing of spinach or mache.

Source and methodology

State zone spans from the USDA Plant Hardiness Zone Map (2023); frost-date averages from NOAA Climate Data Online. Hot-state two-season timing cross-checked against the UF/IFAS Florida Gardening Calendar and the University of Arizona Cooperative Extension planting calendar. Curated by the Growli editorial team.