Garlic (overwintering allium) is classed fall planted in the cited extension guidance. The timing rules below are relative to your local freeze dates — enter a location to turn them into calendar dates.
The rules this site applies
Method
Frost-relative window
Rule & reconciliation
Fall planting
(plant cloves)
1–2 weeks after the median first fall freeze
Minnesota: plant cloves in the fall, usually one or two weeks AFTER the first killing frost (before the ground freezes). Harvest is the following summer.
No start seeds indoors window: Garlic is grown from cloves planted in fall, not from seed or spring transplants.
Variety assumption: Overwinters in the ground; bulbs are harvested the following summer.