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When to Plant Peppers in Clark 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.

Clark County, Wisconsin is in USDA Zone 4a. The average last spring frost is May 13 and the first fall frost is September 30, giving you a growing season of approximately 140 days.

At an elevation of 850 feet, Clark County receives approximately 39.8 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.

Clark County, WI (Zone 4a) Short season
140 days
Last Spring Frost May 13
140 growing days
First Fall Frost September 30

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

6.1-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Start indoors: Feb 17 Transplant: May 26 🍅 Harvest: Jul 28 – Oct 6
Recommended (50%) ✗ May not fit
Start indoors: Feb 25 Transplant: Jun 3 🍅 Harvest: Aug 5 – Oct 14
Safe Start (90%) ✗ May not fit
Start indoors: Mar 5 Transplant: Jun 11 🍅 Harvest: Aug 13 – Oct 22

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 Clark County

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

Soil pH

Your soil pH (6.1โ€“6.8) is within Peppers's preferred range (6.0โ€“7.0).

Soil Texture

The silt loam soil in Clark County is excellent for Peppers โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.9%). Annual compost additions will help Peppers.

How to Plant Peppers

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

Succession Planting Peppers

2
successive plantings in your 140-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 โ€” 1.8" 0" โ„๏ธ Dormant
Feb โ€” 2" 0" โ„๏ธ Dormant
Mar โ€” 2.6" 0" โ„๏ธ Dormant
Apr โ€” 3.9" 0" โ„๏ธ Dormant
May 4.8" 4.6" 0.2" ๐Ÿ’ง Light watering
Jun 4.8" 4.6" 0.2" ๐Ÿ’ง Light watering
Jul 4.8" 4.2" 0.6" ๐Ÿ’ง Light watering
Aug 4.8" 4.2" 0.6" ๐Ÿ’ง Light watering
Sep 4.8" 3.7" 1.1" ๐Ÿ’ง Light watering
Oct โ€” 2.8" 0" โ„๏ธ Dormant
Nov โ€” 3" 0" โ„๏ธ Dormant
Dec โ€” 2.4" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Sep in Clark County). Supplement amounts are based on average rainfall โ€” 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" โ€” every day above 50ยฐF 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 ~862 GDD — county provides 1,610 GDD Excellent fit

Peppers Planting Timeline โ€” Clark County, WI

Peppers Planting Calendar

Activity When Date Range
Start Indoors February 25 Feb 25 โ€“ Mar 11
Transplant Outdoors June 3 Jun 3 โ€“ Jun 17
Direct Sow May 27 May 27 โ€“ Jun 17
Harvest August 5 Aug 5 โ€“ Oct 14

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 Direct Sow
June Transplant Outdoors Direct Sow
July โ€”
August Harvest
September Harvest
October Harvest
November โ€”
December โ€”

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1.1"/week ยท Natural rainfall sufficient

๐Ÿ“… Days to Maturity

60โ€“90 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 4a

๐Ÿ“† Growing Season

140 days in Clark County

Growing Tips for Peppers in Clark County

Direct sow Peppers outdoors after May 13 in Clark 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 Clark County

Fast-maturing pepper varieties for shorter seasons

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

Companion Planting

Good Companions

Avoid Planting Near

  • Fennel
  • Kohlrabi

Check more plant combinations with our Companion Planting Checker →

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 Clark County, WI?

Clark County is in Zone 4a with an average last frost of May 13. Plan your Peppers planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Clark County, WI?

Clark County, Wisconsin is in USDA Hardiness Zone 4a. The average last spring frost is May 13 and first fall frost is September 30.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Clark County gardeners in Zone 4a 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 Clark County, WI. Local conditions may vary. Last updated: April 2026.