Frost dates for Port Huron, 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
April 19
typical year
Safe to plant
May 4
frost is over in 9 of 10 years
First fall frost
November 3
typical year
Growing season
196 days
frost-free, typical year
Frost watch this week
Tonight's and the next six nights' lows from the National Weather Service forecast for the station's location. Frost: 32°F or colder. Possible frost: 33–36°F, mostly in low spots on clear, still nights.
When to plant
Counted from this page's frost dates. Warm-season crops wait for the safe-to-plant date.
| Crop | Start indoors | Plant outside | Fall planting |
|---|---|---|---|
| Cool-season crops | |||
| Peas | – | Mar 22 – Apr 5 | – |
| Spinach | – | Mar 8 – 29 | Sep 8 – 22 |
| Lettuce | – | Mar 22 – Apr 12 | Sep 8 – 22 |
| Radishes | – | Mar 22 – May 3 | Sep 22 – Oct 6 |
| Onions | – | Mar 22 – Apr 5 | – |
| Potatoes | – | Mar 29 – Apr 12 | – |
| Carrots | – | Mar 29 – Apr 19 | Aug 11 – 25 |
| Beets | – | Mar 22 – Apr 5 | Aug 25 – Sep 8 |
| Kale | Feb 8 – 22 | Mar 22 – Apr 5 | Aug 25 – Sep 8 |
| Broccoli | Feb 8 – 22 | Apr 5 – 19 | Aug 25 – Sep 8 |
| Cabbage | Jan 25 – Feb 8 | Mar 22 – Apr 5 | Aug 25 – Sep 8 |
| Garlic | – | – | Sep 22 – Oct 13 |
| Warm-season crops | |||
| Tomatoes | Mar 9 – 23 | May 4 – 18 | – |
| Peppers | Mar 2 – 16 | May 11 – 25 | – |
| Cucumbers | – | May 4 – 25 | – |
| Zucchini | – | May 4 – Jun 1 | – |
| Pumpkins | – | May 4 – 25 | – |
| Green beans | – | May 4 – Aug 25 | – |
| Sweet corn | – | May 4 – Jun 1 | – |
| Basil | Mar 30 – Apr 13 | May 11 – 18 | – |
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 10 | Half of years | 9 years in 10 | |
|---|---|---|---|
| Spring frost after | May 4 | April 19 | April 7 |
| Fall frost before | October 20 | November 3 | November 16 |
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 7 (April 21 in a late year), and the first one in fall around November 12.
Towns that use these dates
This is the nearest NOAA station with frost records for 3 towns.
Port Huron, Marysville, St. Clair
Where these dates come from
NOAA weather station PORT HURON, MI US (USC00206680), 1991–2020 climate normals. It's the nearest station for 6 zip codes, all within 10 miles:
48040, 48049, 48059, 48060, 48074, 48079
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.