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When to Plant Peppers in Trempealeau County, WI

Trempealeau County, Wisconsin Zone 4b April

Your April gardening checklist

Each item below is timed to Trempealeau County, Wisconsin's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost May 15
Avg. first frost September 30
Soil temp (4") 40°F
Watering Low
Pest pressure Low
Daylight 13.2 hrs
Coming up in May — start thinking about
  • Direct-sowing: peppers

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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.

Trempealeau County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 15 and the first fall frost is September 30, giving you a growing season of approximately 138 days.

At an elevation of 1,222 feet, Trempealeau County receives approximately 39.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Peppers to ensure they mature before fall.

Trempealeau County, WI (Zone 4b) Short season
138 days
Last Spring Frost May 15
138 growing days
First Fall Frost September 30

Trempealeau County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-7.2

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 21 Transplant: May 30 🍅 Harvest: Aug 1 – Oct 10
Recommended (50%) ✗ May not fit
Start indoors: Feb 27 Transplant: Jun 5 🍅 Harvest: Aug 7 – Oct 16
Safe Start (90%) ✗ May not fit
Start indoors: Mar 6 Transplant: Jun 12 🍅 Harvest: Aug 14 – Oct 23

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.

Soil Compatibility in Trempealeau County

How your county's soil matches Peppers's growing requirements.

Soil pH

Your soil pH (5.7–7.2) overlaps with Peppers's range (6.0–7.0), though not a perfect match.

Soil Texture

The silt loam soil in Trempealeau County is excellent for Peppers — good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is excellent (4.4%) — Peppers will thrive.

How to Plant Peppers

1"
Planting Depth
15"
Between Plants
24"
Between Rows

Succession Planting Peppers

2
successive plantings in your 138-day season

Sow every 6.9 weeks. Last sowing by Jul 02 to harvest before frost.

Plant Water Budget

Plant needs
1.1″/week
Rainfall provides
1.2″/week
Watering frequency Natural rainfall sufficient
Season total 0 gal / 100 sq ft

Monthly Watering Guide for Peppers

Peppers needs approximately 1.1 inches of water per week (4.8" per month). Here's how your county's rainfall compares month by month.

Month Peppers Needs Rainfall You Supplement Action
Jan 1.6" 0" ❄️ Dormant
Feb 1.8" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 4.1" 0" ❄️ Dormant
May 4.8" 4.4" 0.4" 💧 Light watering
Jun 4.8" 4.9" 0" ✅ Rainfall sufficient
Jul 4.8" 4.2" 0.6" 💧 Light watering
Aug 4.8" 4.1" 0.7" 💧 Light watering
Sep 4.8" 3.5" 1.3" 💧 Light watering
Oct 3.6" 0" ❄️ Dormant
Nov 2.7" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

Water needs are for active growing months only (May–Sep in Trempealeau County). Supplement amounts are based on average rainfall — actual needs vary with temperature, soil, and mulching.

Peppers Heat Requirements (GDD)

What are Growing Degree Days (GDD)?

Growing Degree Days measure the total warmth your plants receive during the growing season. Think of it as a "heat bank" — every day above 50°F deposits warmth that helps your plants grow.

Each plant needs a certain amount of accumulated heat to mature. If your county provides more GDD than the plant needs, it's a great fit. If it's close, you may want to choose faster-maturing varieties or start seeds indoors to get a head start.

Peppers needs ~806 GDD — county provides 1,483 GDD Excellent fit

Peppers Planting Timeline — Trempealeau County, WI

Peppers Planting Calendar

Activity When Date Range
Start Indoors February 27 Feb 27 – Mar 13
Transplant Outdoors June 5 Jun 5 – Jun 19
Direct Sow May 29 May 29 – Jun 19
Harvest August 7 Aug 7 – Oct 16

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1.1"/week · Natural rainfall sufficient

📅 Days to Maturity

60–90 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 4b

📆 Growing Season

138 days in Trempealeau County

Growing Tips for Peppers in Trempealeau County

Direct sow Peppers outdoors after May 15 in Trempealeau County when soil has warmed and frost danger has passed.

Common pests for Peppers in this region include tomato hornworm and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

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.

Recommended Peppers Varieties for Trempealeau County

Fast-maturing pepper varieties for shorter seasons

Ace (50d) Gypsy (58d) Early Jalapeño (60d)

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Check more plant combinations with our Companion Planting Checker →

🌾 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 35°F, under 50% humidity.

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

Frequently Asked Questions

When should I plant Peppers in Trempealeau County, WI?

Trempealeau County is in Zone 4b with an average last frost of May 15. Plan your Peppers planting based on this frost date — see the calendar above for exact timing.

What planting zone is Trempealeau County, WI?

Trempealeau County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 15 and first fall frost is September 30.

🌱

Your Trempealeau County Garden Planner — Free

A 24-page printable planner built for Trempealeau County (Zone 4b). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

Every number on this page traces back to a primary horticulture or government data source. Click through to verify.