Frost dates for Ontonagon, 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 27
typical year
Safe to plant
June 13
frost is over in 9 of 10 years
First fall frost
October 1
typical year
Growing season
127 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 | – | Apr 29 – May 13 | – |
| Spinach | – | Apr 15 – May 6 | Aug 6 – 20 |
| Lettuce | – | Apr 29 – May 20 | Aug 6 – 20 |
| Radishes | – | Apr 29 – Jun 10 | Aug 20 – Sep 3 |
| Onions | – | Apr 29 – May 13 | – |
| Potatoes | – | May 6 – 20 | – |
| Carrots | – | May 6 – 27 | Jul 9 – 23 |
| Beets | – | Apr 29 – May 13 | Jul 23 – Aug 6 |
| Kale | Mar 18 – Apr 1 | Apr 29 – May 13 | Jul 23 – Aug 6 |
| Broccoli | Mar 18 – Apr 1 | May 13 – 27 | Jul 23 – Aug 6 |
| Cabbage | Mar 4 – 18 | Apr 29 – May 13 | Jul 23 – Aug 6 |
| Garlic | – | – | Aug 20 – Sep 10 |
| Warm-season crops | |||
| Tomatoes | Apr 18 – May 2 | Jun 13 – 27 | – |
| Peppers | Apr 11 – 25 | Jun 20 – Jul 4 | – |
| Cucumbers | – | Jun 13 – Jul 4 | – |
| Zucchini | – | Jun 13 – Jul 11 | – |
| Pumpkins | – | Jun 13 – Jul 4 | – |
| Green beans | – | Jun 13 – Jul 23 | – |
| Sweet corn | – | Jun 13 – Jul 11 | – |
| Basil | May 9 – 23 | Jun 20 – 27 | – |
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 | June 13 | May 27 | May 7 |
| Fall frost before | September 14 | October 1 | October 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 May 10 (May 29 in a late year), and the first one in fall around October 14.
Towns that use these dates
This is the nearest NOAA station with frost records for 1 town.
Ontonagon
Where these dates come from
NOAA weather station ONTONAGON 6 SE, MI US (USC00206220), 1991–2020 climate normals. It's the nearest station for 2 zip codes, all within 11 miles:
49953, 49960
Planting dates follow common university extension advice; your local extension service can fine-tune them for your soil and microclimate.