Winthrop, MN frost dates
How Winthrop compares
- In 8 years out of 10, the last spring frost in Winthrop falls between April 9 and May 8, a 29-day window. The first fall frost falls between September 30 and October 27.
- The median last frost is 11 days earlier than the Minnesota median of May 5.
- Its 174-day growing season is longer than 95% of the 801 Minnesota places with a regular frost season (state median 151 days).
- The last frost is 14 days earlier than the zone 4b median of May 8. Hardiness zones measure winter cold, not season length, so use these dates rather than a zone 4b chart.
- The weather station records an average of 161 nights a year at or below 32°F.
- Compared with Eden Prairie, MN, 80 km away, the last frost here is 1 day later than there and the growing season is the same length.
Frost probability
| Chance of frost after | Date |
|---|---|
| 90% (early) | April 9 |
| 50% (median) | April 24 |
| 10% (safe for tender plants) | May 8 |
| Chance of frost before | Date |
|---|---|
| 10% (early) | September 30 |
| 50% (median) | October 15 |
| 90% (late) | October 27 |
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 Winthrop, MN
Winthrop, MN frost dates — last frost Apr 24, first frost Oct 15, zone 4b. whenisthelastfrost.com
When to plant vegetables in Winthrop, MN
| Crop | Start indoors | Transplant | Sow outdoors | Fall crop |
|---|---|---|---|---|
| Onions | Jan 30 – Feb 13 | Mar 27 – Apr 10 | — | — |
| Peppers | Feb 13 – Feb 27 | May 8 – May 22 | — | — |
| Eggplant | Feb 13 – Feb 27 | May 8 – May 22 | — | — |
| Tomatoes | Feb 27 – Mar 13 | May 1 – May 15 | — | — |
| Lettuce | Feb 27 – Mar 13 | Apr 3 – Apr 17 | Mar 27 – May 1 | Aug 20 – Sep 17 |
| Kale | Feb 27 – Mar 13 | Mar 27 – Apr 10 | Mar 27 – Apr 10 | Aug 6 – Aug 27 |
| Broccoli | Feb 27 – Mar 13 | Apr 10 – Apr 24 | — | Jul 9 – Jul 30 |
| Cabbage | Feb 27 – Mar 13 | Apr 3 – Apr 17 | — | Jul 9 – Jul 30 |
| Cauliflower | Feb 27 – Mar 13 | Apr 10 – Apr 24 | — | Jul 9 – Jul 30 |
| Okra | Mar 13 – Mar 27 | May 15 – May 29 | May 15 – May 29 | — |
| Basil | Mar 13 – Mar 27 | May 1 – May 15 | — | — |
| Peas | — | — | Mar 13 – Apr 3 | Jul 23 – Aug 13 |
| Spinach | — | — | Mar 13 – Apr 3 | Aug 20 – Sep 10 |
| Radishes | — | — | Mar 20 – May 1 | Sep 3 – Sep 24 |
| Cucumbers | Mar 27 – Apr 3 | May 8 – May 15 | May 1 – May 15 | Jul 30 – Aug 13 |
| Zucchini & Summer Squash | Mar 27 – Apr 3 | — | May 1 – May 15 | Aug 6 – Aug 20 |
| Winter Squash & Pumpkins | Mar 27 – Apr 3 | — | May 1 – May 15 | — |
| Melons & Watermelon | Mar 27 – Apr 3 | May 8 – May 22 | — | — |
| Carrots | — | — | Apr 3 – May 1 | Jul 23 – Aug 6 |
| Beets | — | — | Apr 3 – May 1 | Aug 6 – Aug 20 |
| Potatoes | — | — | Apr 3 – Apr 24 | — |
| Swiss Chard | — | — | Apr 10 – May 8 | Aug 6 – Aug 20 |
| Cilantro | — | — | Apr 10 – May 1 | Aug 20 – Sep 10 |
| Green Beans | — | — | May 1 – May 22 | Jul 30 – Aug 13 |
| Sweet Corn | — | — | May 1 – May 15 | — |
| Sweet Potatoes | — | May 8 – May 29 | — | — |
| Garlic | — | — | — | Oct 1 – Nov 5 |
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 Gaylord, MN weather station, 12 km away (elevation 1,020 ft (311 m)).
Frost dates near Winthrop
- Gaylord Apr 24 · Oct 15
- Gibbon Apr 30 · Oct 4
- Lafayette Apr 29 · Oct 7
- New Auburn Apr 30 · Oct 4
- Brownton Apr 30 · Oct 4
- Stewart Apr 30 · Oct 4
- Arlington Apr 24 · Oct 15
- New Ulm Apr 29 · Oct 7
- Fairfax Apr 30 · Oct 4
- Courtland May 2 · Oct 7
Frequently asked questions
When is the last frost in Winthrop, MN?
The median last spring frost in Winthrop, MN is April 24. There is still about a 10% chance of frost after May 8, so wait until then to plant frost-tender crops like tomatoes and peppers.
When is the first frost in Winthrop, MN?
The median first fall frost is October 15, with about a 10% chance of frost before September 30.
How long is the growing season in Winthrop, MN?
About 174 days between the median last spring frost and first fall frost.
What planting zone is Winthrop, MN?
Winthrop, MN is in USDA hardiness zone 4b.