When to Plant Pumpkins in Wisconsin
From jack-o-lanterns to pies, pumpkins need space and time but deliver a uniquely satisfying harvest.
The Short Answer
Wisconsin Frost Dates
Your planting dates depend on which part of Wisconsin you're in. Here are the frost date ranges by region:
| Region | Zones | Last Frost (Spring) | First Frost (Fall) |
|---|---|---|---|
| Northern Wisconsin | 3b, 4a | May 15 - Jun 1 | Sep 10 - Sep 25 |
| Central Wisconsin | 4a, 4b | May 5 - May 20 | Sep 20 - Oct 5 |
| Southern Wisconsin | 4b, 5a, 5b | Apr 25 - May 10 | Oct 1 - Oct 15 |
Pumpkins Planting Schedule for Wisconsin
Northern Wisconsin (Zones 3b, 4a)
Average last frost: May 15 - Jun 1 · Average first frost: Sep 10 - Sep 25
Central Wisconsin (Zones 4a, 4b)
Average last frost: May 5 - May 20 · Average first frost: Sep 20 - Oct 5
Southern Wisconsin (Zones 4b, 5a, 5b)
Average last frost: Apr 25 - May 10 · Average first frost: Oct 1 - Oct 15
Growing Pumpkins in Wisconsin
Pumpkins in Wisconsin's Climate
Pumpkin growing is a calendar countdown — count backward from your target harvest date (usually mid-October for Halloween) using your variety's days-to-maturity. In short-season zones, choose 90-day varieties and start seeds indoors 3 weeks before last frost. Black plastic mulch warms soil for earlier transplanting. Squash vine borer is less common in cold zones — a genuine advantage.
Soil Considerations for Wisconsin
Rich agricultural soils in southern half. Sandy soils in central plain. Heavy clay in some lake regions. Generally fertile. Make sure soil has warmed to at least 65°F before planting pumpkins outside.
Wisconsin Climate & Growing Season
Cold winters. Warm summers. Lake Michigan moderates eastern climate. Good growing season in south. Short season in north. Pumpkins cannot tolerate any frost, so wait until all frost danger has passed before transplanting outside. Watch local forecasts carefully in spring.
Growing season length varies across Wisconsin: Northern Wisconsin (3b, 4a) has a last frost around May 15 - Jun 1, while Southern Wisconsin (4b, 5a, 5b) sees frost end around Apr 25 - May 10. This difference matters for pumpkins — transplant timing shifts by several weeks across the state.
Growing Tips
Count backwards from when you want ripe pumpkins (usually October). They need 90-120 days, so mid-June to early July is often ideal.
Companion Planting
Plant pumpkins alongside these companions for better growth:
Keep pumpkins away from:
The Bottom Line
Last reviewed: March 29, 2026