Michigan · zones 4b6b

When to plant garlic in Michigan.

Michigan's window for garlic runs on the fall side of the season. A second, fall sowing fits Oct 8 to Oct 23. Dates below are state medians; your ZIP code shifts them by days to weeks.

The 2026 windows

Garlic dates for a typical Michigan season.

Fall round

Oct 8 to Oct 23

Counted back from the ~Oct 8 first frost.

Harvest

~240 days later

~0.2 lb per plant over ~1 weeks.

Michigan spans more than one climate: Zone 6 is the most common zone, but the state runs 4b to 6b. That's why the planner works from your ZIP code's frost dates, not your zone: mountain and coastal gardens in the same state can be three weeks apart.

In Michigan: watch for

The pests that find garlic here.

A middle-length season, about 156 frost-free days, means garlic overlaps onion thrips for a stretch each summer. Check plants every week or two and treat early.

Onion thrips

Silvery streaks and curled leaf tips in hot spells.

Organic fix: Insecticidal soap or neem; hang sticky traps.

Onion maggot

Seedlings wilt; white maggots in the bulb base.

Organic fix: Float a row cover over the row; rotate beds each year.

Downy mildew

Pale patches with fuzzy gray growth in damp weather.

Organic fix: Space for airflow, water early in the day, spray neem.

White rot

Yellowing and dieback, then wilt; fluffy white mold at the bulb base and roots so rotted the plant lifts straight out.

Organic fix: No cure once it is in the soil. Plant clean stock, never follow onions with onions, and keep infested soil off tools and boots.

Your season math: Michigan gives garlic about 156 frost-free days, and it needs roughly 240 days to a first harvest. It's a one-planting crop, so time that single sowing well.

Planting garlic in Michigan: questions

When should I plant garlic in Michigan?+

Michigan's window for garlic is in fall: Oct 8 to Oct 23, keyed to the first fall frost around Oct 8.

What USDA zone is Michigan?+

Michigan spans zones 4b–6b, mostly zone 6. But frost dates, not zones, set planting time. The free planner uses your ZIP code's actual frost dates.

How many garlic plants do I need?+

Depends who you're feeding. The crop page has exact counts per household size, or the free planner does the math for your family in about 60 seconds.