Marquette, MI Frost Dates & Growing Season

The two dates every Marquette garden is planned around, plus ready-computed planting windows for the most popular crops.

Last spring frost
May 8
~50% chance of frost after
First fall frost
Oct 21
~50% chance of frost before
Growing season
166 days
frost-free stretch
USDA zone
5a
2023 hardiness map
Risky (1 year in 10)MedianSafe (9 years in 10)
Last spring frost Apr 26 May 8 May 23
First fall frost Nov 5 Oct 21 Oct 6
Hard freeze (28°F), median last Apr 27 · first Nov 2

Computed from NOAA 1991–2020 climate normals at the Marquette station (2 km from central Marquette). "Safe" means frost past that date happens only about one year in ten. Your exact garden can still run days either way with elevation and terrain — check your own ZIP with the frost date lookup.

Planting windows for Marquette

Computed from Marquette's own frost dates. Click any crop for the full zone-5 growing guide — varieties, spacing, fall plantings, and more.

CropStart seeds indoorsTransplantDirect sow
🍅 Tomatoes Mar 13 – Mar 27 May 15 – May 22
🫑 Peppers Feb 27 – Mar 13 May 22 – May 29
🥬 Lettuce Mar 27 – Apr 10 Apr 10 – Apr 24 Apr 10 – May 8
🫛 Peas Mar 27 – Apr 10
🥕 Carrots Apr 17 – May 8
🥦 Broccoli Mar 20 – Apr 3 Apr 17 – May 1
🥬 Kale Mar 27 – Apr 10 Apr 10 – Apr 24 Apr 10 – Apr 24
🥒 Cucumbers Apr 10 – Apr 17 May 15 – May 22 May 15 – May 22
🥒 Zucchini Apr 10 – Apr 17 May 15 – May 22 May 15 – May 22
🫘 Green Beans (Bush) May 15 – May 22
🌽 Sweet Corn May 15 – May 22
🌿 Basil Mar 27 – Apr 10 May 15 – May 22 May 22 – May 29
🧄 Garlic Fall: Sep 9 – Oct 7

Want this for all 50 crops, or as a printable seed-shelf schedule? Use the planting calendar and the seed starting scheduler — both can use Marquette's dates automatically after a lookup.

Reading the season in Marquette

Roughly 166 frost-free days gives Marquette gardeners room for nearly every common vegetable. Warm-season crops go out after May 8; a fall garden sown in late summer matures comfortably before the Oct 21 frost.

Frequently asked questions

When is the last frost in Marquette, MI?

The average last spring frost in Marquette is around May 8, based on 1991–2020 climate normals. That's a median — about half of years see a later frost, so tender crops are safest going out a week or two after this date.

When is the first frost in Marquette, MI?

The average first fall frost in Marquette arrives around Oct 21. Crops still in the garden need to mature before then, and frost-tender plants need harvesting or protection as the date approaches.

How long is the growing season in Marquette?

About 166 frost-free days on average, from May 8 to Oct 21. That fits nearly all common vegetables, though the longest-season melons and sweet potatoes benefit from transplants.

What USDA zone is Marquette in?

USDA zone 5a on the 2023 Plant Hardiness Zone Map. Note that zones describe winter cold, not frost timing — these frost dates are the numbers to plan plantings around.