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When to Plant Peppers in Kewaunee County, WI

Sweet peppers are warm-season crops producing fruits in a rainbow of colors. They turn from green to red, yellow, or orange as they ripen, increasing in sweetness.

Kewaunee County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 3 and the first fall frost is October 11, giving you a growing season of approximately 161 days.

At an elevation of 950 feet, Kewaunee County receives approximately 39.9 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82ยฐF, so choose short-season varieties of Peppers to ensure they mature before fall.

Kewaunee County, WI (Zone 4b) Moderate season
161 days
Last Spring Frost May 3
161 growing days
First Fall Frost October 11

Kewaunee County Soil Profile

Soil Type

Silt Loam

Soil pH

5.8-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (5 days to spare)
Start indoors: Feb 9 Transplant: May 18 🍅 Harvest: Jul 20 – Sep 28
Recommended (50%) ✓ Fits season (7 days to spare)
Start indoors: Feb 15 Transplant: May 24 🍅 Harvest: Jul 26 – Oct 4
Safe Start (90%) ✓ Fits season (6 days to spare)
Start indoors: Mar 4 Transplant: Jun 10 🍅 Harvest: Aug 12 – Oct 21

Percentages indicate frost risk at transplant. The 70% safe window means there is a 30% chance of frost after transplant — suitable for cold-hardy crops or gardeners with frost protection. The 90% safe window is best for tender plants.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Peppers needs ~862 GDD — county provides 1,851 GDD Excellent fit

Peppers Planting Timeline โ€” Kewaunee County, WI

Peppers Planting Calendar

Activity When Date Range
Start Indoors February 15 Feb 15 โ€“ Mar 1
Transplant Outdoors May 24 May 24 โ€“ Jun 7
Direct Sow May 17 May 17 โ€“ Jun 7
Harvest July 26 Jul 26 โ€“ Oct 4

Plant 1" deep ยท 15" apart ยท Rows 24" apart

Month-by-Month Timeline

MonthActivities
January โ€”
February Start Indoors
March Start Indoors
April โ€”
May Transplant Outdoors Direct Sow
June Transplant Outdoors Direct Sow
July Harvest
August Harvest
September Harvest
October Harvest
November โ€”
December โ€”

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

60โ€“90 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 4b

Growing Season

161 days

Growing Tips for Kewaunee County

Start seeds indoors 8-10 weeks before last frost. Transplant when nighttime temperatures stay above 55F. Avoid high-nitrogen fertilizers which promote leaves over fruit.

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Level Up Your Garden

๐ŸŒพ Save Your Own Peppers Seeds
Life Cycle Annual
Pollination Self-Pollinating
How to Collect Remove seeds from fully ripe (red/orange) fruit.
Storage Store airtight; viable 4 years at 35ยฐF, under 50% humidity.

Isolate 300 ft for purity. Hot and sweet peppers can cross-pollinate.

Frequently Asked Questions

When should I plant Peppers in Kewaunee County, WI?

Kewaunee County is in Zone 4b with an average last frost of May 3. Plan your Peppers planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Kewaunee County, WI?

Kewaunee County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 3 and first fall frost is October 11.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Kewaunee County gardeners in Zone 4b organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals. Frost dates are based on 50% probability averages for Kewaunee County, WI. Local conditions may vary. Last updated: April 2026.