Duluth, Minnesota frost dates
Frost risk by date
| Chance of frost | Spring: frost after | Fall: frost before |
|---|---|---|
| 90% | April 29 | October 16 |
| 70% | May 6 | October 7 |
| 50% | May 13 | October 1 |
| 30% | May 19 | September 26 |
| 10% | May 29 | September 18 |
Read the spring column like this: there is a 10% chance of a 32°F freeze after May 29. These are NOAA probabilities for the Duluth weather station (USW00014913, elevation 435 m), 1991–2020.
Duluth vegetable planting calendar
Dates count from the 50% last-frost date (May 13). For tomatoes, peppers and other frost-tender crops, waiting until the 10% date (May 29) is the cautious choice.
| Crop | Start seeds indoors | Plant out |
|---|---|---|
| Beans | Apr 22 | May 20 (usually sown directly in the garden) |
| Broccoli | Mar 4 | Apr 15 |
| Brussels sprouts | Mar 4 | Apr 15 |
| Cabbage | Feb 25 | Apr 8 |
| Cauliflower | Mar 18 | Apr 29 |
| Sweet corn | Apr 15 | May 13 (usually sown directly in the garden) |
| Cucumbers | Apr 29 | May 20 |
| Kale | Feb 25 | Apr 8 |
| Leeks | Jan 28 | Apr 8 |
| Lettuce | Mar 25 | Apr 29 |
| Melons | May 6 | May 27 |
| Onions | Jan 21 | Apr 1 (from seed; sets and transplants go out at the same time) |
| Peas | Mar 18 | Apr 15 (usually sown directly in the garden) |
| Peppers | Apr 1 | May 27 |
| Squash | May 6 | May 27 |
| Tomatoes | Mar 18 | May 13 |
Offsets from Oregon State University Extension's seed-starting table. "Plant out" means transplant, or sow directly for crops usually grown from seed.
Fall frost and season extension
The first fall freeze usually arrives around October 1. There's a 1-in-10 chance it comes before September 18. Harvest tender crops such as basil, tomatoes, peppers and squash before then, or cover them on cold nights. Cool-season crops like kale, cabbage and Brussels sprouts handle light frost, and often taste sweeter after it. A hard freeze (28°F) typically comes around October 13.
Nearby cities
| City | Last frost (50%) | First frost (50%) | Distance |
|---|---|---|---|
| Minneapolis, MN | Apr 23 | Oct 18 | ~230 km |
| Fargo, ND | May 10 | Sep 30 | ~350 km |
| Green Bay, WI | Apr 30 | Oct 9 | ~405 km |
| Madison, WI | May 1 | Oct 10 | ~464 km |
| Sioux Falls, SD | May 1 | Oct 6 | ~498 km |
| Milwaukee, WI | Apr 19 | Oct 29 | ~541 km |