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When to Plant Kidney Beans in Sauk County, WI

Kidney beans are a popular dry bean variety named for their shape, available in red and white types. They are the classic bean for chili and red beans and rice.

Sauk County, Wisconsin is in USDA Zone 4b. The average last spring frost is May 3 and the first fall frost is October 7, giving you a growing season of approximately 157 days.

At an elevation of 1,002 feet, Sauk County receives approximately 30.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81ยฐF, so choose short-season varieties of Kidney Beans to ensure they mature before fall.

Sauk County, WI (Zone 4b) Moderate season
157 days
Last Spring Frost May 3
157 growing days
First Fall Frost October 7

Sauk County Soil Profile

Soil Type

Silt Loam

Soil pH

6-6.7

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (32 days to spare)
Transplant: Apr 27 🍅 Harvest: Jul 27 – Aug 31
Recommended (50%) ✓ Fits season (31 days to spare)
Transplant: May 3 🍅 Harvest: Aug 2 – Sep 6
Safe Start (90%) ✓ Fits season (24 days to spare)
Transplant: May 21 🍅 Harvest: Aug 20 – Sep 24

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 Sauk County

How your county's soil matches Kidney Beans's growing requirements.

Soil pH

Your soil pH (6.0โ€“6.7) is within Kidney Beans's preferred range (6.0โ€“7.5).

Soil Texture

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

Organic Matter

Organic matter is excellent (4.7%) โ€” Kidney Beans will thrive.

How to Plant Kidney Beans

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.8″/week
You supply
0.2″/week
Watering frequency Only during dry spells
Season total 265 gal / 100 sq ft

Monthly Watering Guide for Kidney Beans

Kidney Beans needs approximately 1 inches of water per week (4.3" per month). Here's how your county's rainfall compares month by month.

Month Kidney Beans Needs Rainfall You Supplement Action
Jan โ€” 1.3" 0" โ„๏ธ Dormant
Feb โ€” 1.3" 0" โ„๏ธ Dormant
Mar โ€” 2.2" 0" โ„๏ธ Dormant
Apr โ€” 3.3" 0" โ„๏ธ Dormant
May 4.3" 3.4" 0.9" ๐Ÿ’ง Light watering
Jun 4.3" 4" 0.3" ๐Ÿ’ง Light watering
Jul 4.3" 2.9" 1.4" ๐Ÿ’ง Light watering
Aug 4.3" 3.6" 0.7" ๐Ÿ’ง Light watering
Sep 4.3" 2.3" 2" ๐Ÿ’ง Light watering
Oct 4.3" 2.1" 2.2" ๐Ÿšฟ Regular watering
Nov โ€” 2.3" 0" โ„๏ธ Dormant
Dec โ€” 1.8" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Mayโ€“Oct in Sauk County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Kidney Beans 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.

Kidney Beans needs ~1,048 GDD — county provides 1,687 GDD Excellent fit

Kidney Beans Planting Timeline โ€” Sauk County, WI

Kidney Beans Planting Calendar

Activity When Date Range
Direct Sow May 17 May 17 โ€“ Jun 7
Harvest August 16 Aug 16 โ€“ Sep 20

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

1"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

85โ€“110 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: ideal

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

157 days in Sauk County

Growing Tips for Kidney Beans in Sauk County

Direct sow Kidney Beans outdoors after May 03 in Sauk County when soil has warmed and frost danger has passed.

Common pests for Kidney Beans in this region include bean beetles and aphids. Use row covers early in the season and inspect plants weekly.

General growing tips

Direct sow after frost. Allow pods to dry completely on the plant. Kidney beans must be thoroughly cooked as raw or undercooked beans contain harmful lectins.

Companion Planting

Good Companions

Avoid Planting Near

  • Onion
  • Garlic

Check more plant combinations with our Companion Planting Checker →

Frequently Asked Questions

When should I plant Kidney Beans in Sauk County, WI?

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

What planting zone is Sauk County, WI?

Sauk County, Wisconsin is in USDA Hardiness Zone 4b. The average last spring frost is May 3 and first fall frost is October 7.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Sauk 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 Sauk County, WI. Local conditions may vary. Last updated: April 2026.