Frost Report

All states Michigan

Frost dates for Mackinaw City, MI

When the last spring frost and first fall frost usually come, and when to plant, from 30 years of NOAA weather records.

Last spring frost

May 7

typical year

Safe to plant

May 22

frost is over in 9 of 10 years

First fall frost

October 23

typical year

Growing season

167 days

frost-free, typical year

When to plant

Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.

CropStart indoorsPlant outsideFall planting
Cool-season crops
Peas – Apr 9 – 23 –
Spinach – Mar 26 – Apr 16 Aug 28 – Sep 11
Lettuce – Apr 9 – 30 Aug 28 – Sep 11
Radishes – Apr 9 – May 21 Sep 11 – 25
Onions – Apr 9 – 23 –
Potatoes – Apr 16 – 30 –
Carrots – Apr 16 – May 7 Jul 31 – Aug 14
Beets – Apr 9 – 23 Aug 14 – 28
Kale Feb 26 – Mar 12 Apr 9 – 23 Aug 14 – 28
Broccoli Feb 26 – Mar 12 Apr 23 – May 7 Aug 14 – 28
Cabbage Feb 12 – 26 Apr 9 – 23 Aug 14 – 28
Garlic – – Sep 11 – Oct 2
Warm-season crops
Tomatoes Mar 27 – Apr 10 May 22 – Jun 5 –
Peppers Mar 20 – Apr 3 May 29 – Jun 12 –
Cucumbers – May 22 – Jun 12 –
Zucchini – May 22 – Jun 19 –
Pumpkins – May 22 – Jun 12 –
Green beans – May 22 – Aug 14 –
Sweet corn – May 22 – Jun 19 –
Basil Apr 17 – May 1 May 29 – Jun 5 –

Onions: from sets. Green beans: until 10 weeks before the first fall frost. Garlic: harvest next summer.

The year at a glance

Start indoors Plant outside Fall planting

The chance of frost, by date

1 year in 10Half of years9 years in 10
Spring frost after May 22May 7April 25
Fall frost before October 6October 23November 6

Frost here means 32°F or colder. Read across: in 1 year in 10, spring frost carries on past the first date, which is why that date is the safe-to-plant date.

Hard freeze (28°F)

A hard freeze kills most garden plants, even hardy ones. The last one in spring usually comes around April 25 (May 10 in a late year), and the first one in fall around November 3.

Towns that use these dates

This is the nearest NOAA station with frost records for 1 town.

Mackinaw City

Where these dates come from

NOAA weather station ST IGNACE MACKINAC BR, MI US (USC00207274), 1991–2020 climate normals. It's the nearest station for 1 zip code, all within 7 miles:

49701

Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.