Carlton, MN frost dates
How Carlton compares
- In 8 years out of 10, the last spring frost in Carlton falls between May 13 and June 9, a 27-day window. The first fall frost falls between September 9 and October 4.
- The median last frost is 21 days later than the Minnesota median of May 5.
- Its 120-day growing season is longer than 4% of the 801 Minnesota places with a regular frost season (state median 151 days).
- The last frost is 14 days later than the zone 4a median of May 12. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4a chart.
- The weather station records an average of 191 nights a year at or below 32°F.
- Compared with Duluth, MN, 30 km away, the last frost here is 12 days later than there and the growing season is 31 days shorter.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | May 13 |
| 50% (median) | May 26 |
| 10% (safe for tender plants) | June 9 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 9 |
| 50% (median) | September 23 |
| 90% (late) | October 4 |
Frost here means 32°F (0°C). A median date means half of years have their last frost earlier and half later.
Planting calendar for Carlton, MN
Carlton, MN frost dates — last frost May 26, first frost Sep 23, zone 4a. whenisthelastfrost.com
When to plant vegetables in Carlton, MN
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Mar 3 – Mar 17 | Apr 28 – May 12 | — | — |
| Peppers | Mar 17 – Mar 31 | Jun 9 – Jun 23 | — | — |
| Eggplant | Mar 17 – Mar 31 | Jun 9 – Jun 23 | — | — |
| Tomatoes | Mar 31 – Apr 14 | Jun 2 – Jun 16 | — | — |
| Lettuce | Mar 31 – Apr 14 | May 5 – May 19 | Apr 28 – Jun 2 | Jul 29 – Aug 26 |
| Kale | Mar 31 – Apr 14 | Apr 28 – May 12 | Apr 28 – May 12 | Jul 15 – Aug 5 |
| Broccoli | Mar 31 – Apr 14 | May 12 – May 26 | — | Jun 17 – Jul 8 |
| Cabbage | Mar 31 – Apr 14 | May 5 – May 19 | — | Jun 17 – Jul 8 |
| Cauliflower | Mar 31 – Apr 14 | May 12 – May 26 | — | Jun 17 – Jul 8 |
| Okra | Apr 14 – Apr 28 | Jun 16 – Jun 30 | Jun 16 – Jun 30 | — |
| Basil | Apr 14 – Apr 28 | Jun 2 – Jun 16 | — | — |
| Peas | — | — | Apr 14 – May 5 | Jul 1 – Jul 22 |
| Spinach | — | — | Apr 14 – May 5 | Jul 29 – Aug 19 |
| Radishes | — | — | Apr 21 – Jun 2 | Aug 12 – Sep 2 |
| Cucumbers | Apr 28 – May 5 | Jun 9 – Jun 16 | Jun 2 – Jun 16 | Jul 8 – Jul 22 |
| Zucchini & Summer Squash | Apr 28 – May 5 | — | Jun 2 – Jun 16 | Jul 15 – Jul 29 |
| Winter Squash & Pumpkins | Apr 28 – May 5 | — | Jun 2 – Jun 16 | — |
| Melons & Watermelon | Apr 28 – May 5 | Jun 9 – Jun 23 | — | — |
| Carrots | — | — | May 5 – Jun 2 | Jul 1 – Jul 15 |
| Beets | — | — | May 5 – Jun 2 | Jul 15 – Jul 29 |
| Potatoes | — | — | May 5 – May 26 | — |
| Swiss Chard | — | — | May 12 – Jun 9 | Jul 15 – Jul 29 |
| Cilantro | — | — | May 12 – Jun 2 | Jul 29 – Aug 19 |
| Green Beans | — | — | Jun 2 – Jun 23 | Jul 8 – Jul 22 |
| Sweet Corn | — | — | Jun 2 – Jun 16 | — |
| Sweet Potatoes | — | Jun 9 – Jun 30 | — | — |
| Garlic | — | — | — | Sep 9 – Oct 14 |
Dates come from the median frost dates and common extension-service timing. Adjust for your soil temperature, microclimate and the varieties you grow.
About these dates
Based on 1991–2020 NOAA climate normals for the Cloquet, MN weather station, 8 km away (elevation 1,266 ft (386 m)).
Frost dates near Carlton
- Wrenshall Jun 1 · Sep 22
- Esko May 26 · Sep 23
- Cloquet May 26 · Sep 23
- Sawyer May 26 · Sep 23
- Barnum May 12 · Oct 2
- Holyoke Jun 1 · Sep 22
- Brookston May 26 · Sep 23
- Saginaw May 18 · Oct 1
- Twig May 18 · Oct 1
- Duluth May 14 · Oct 12
Frequently asked questions
When is the last frost in Carlton, MN?
The median last spring frost in Carlton, MN is May 26. There is still about a 10% chance of frost after June 9, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Carlton, MN?
The median first fall frost is September 23, with about a 10% chance of frost before September 9.
How long is the growing season in Carlton, MN?
About 120 days between the median last spring frost and first fall frost.
What planting zone is Carlton, MN?
Carlton, MN is in USDA hardiness zone 4a.