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When to Plant Kidney Beans in Blue Earth County, MN

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.

Blue Earth County, Minnesota is in USDA Zone 4b. The average last spring frost is April 29 and the first fall frost is October 4, giving you a growing season of approximately 158 days.

At an elevation of 646 feet, Blue Earth County receives approximately 40.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 82ยฐF, so choose short-season varieties of Kidney Beans to ensure they mature before fall.

Blue Earth County, MN (Zone 4b) Moderate season
158 days
Last Spring Frost April 29
158 growing days
First Fall Frost October 4

Blue Earth County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (30 days to spare)
Transplant: Apr 24 🍅 Harvest: Jul 24 – Aug 28
Recommended (50%) ✓ Fits season (32 days to spare)
Transplant: Apr 29 🍅 Harvest: Jul 29 – Sep 2
Safe Start (90%) ✓ Fits season (29 days to spare)
Transplant: May 14 🍅 Harvest: Aug 13 – Sep 17

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 Blue Earth County

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

Soil pH

Your soil pH (5.9โ€“6.8) overlaps with Kidney Beans's range (6.0โ€“7.5), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (4.0%). Annual compost additions will help Kidney Beans.

How to Plant Kidney Beans

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

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
1.1″/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

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€” 1.6" 0" โ„๏ธ Dormant
Feb โ€” 1.9" 0" โ„๏ธ Dormant
Mar โ€” 3.1" 0" โ„๏ธ Dormant
Apr 4.3" 4" 0.3" ๐Ÿ’ง Light watering
May 4.3" 4.3" 0" โœ… Rainfall sufficient
Jun 4.3" 4.3" 0" โœ… Rainfall sufficient
Jul 4.3" 5.1" 0" โœ… Rainfall sufficient
Aug 4.3" 4.4" 0" โœ… Rainfall sufficient
Sep 4.3" 3.2" 1.1" ๐Ÿ’ง Light watering
Oct 4.3" 3.3" 1" ๐Ÿ’ง Light watering
Nov โ€” 2.5" 0" โ„๏ธ Dormant
Dec โ€” 2.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Aprโ€“Oct in Blue Earth 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 ~1,121 GDD — county provides 1,817 GDD Excellent fit

Kidney Beans Planting Timeline โ€” Blue Earth County, MN

Kidney Beans Planting Calendar

Activity When Date Range
Direct Sow May 13 May 13 โ€“ Jun 3
Harvest August 12 Aug 12 โ€“ Sep 16

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 Natural rainfall sufficient

๐Ÿ“… Days to Maturity

85โ€“110 days

๐Ÿงช Soil pH

Needs 6โ€“7.5 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 4b

๐Ÿ“† Growing Season

158 days in Blue Earth County

Growing Tips for Kidney Beans in Blue Earth County

Direct sow Kidney Beans outdoors after April 29 in Blue Earth 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 Blue Earth County, MN?

Blue Earth County is in Zone 4b with an average last frost of April 29. Plan your Kidney Beans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Blue Earth County, MN?

Blue Earth County, Minnesota is in USDA Hardiness Zone 4b. The average last spring frost is April 29 and first fall frost is October 4.

๐ŸŒฑ

Plan Your Garden with Confidence

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