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When to plant Soybeans in Lake County, MN

Plant Soybeans in Lake County during the brief June 15–July 6 window. With 103 frost-free days, fall plantings can't mature before September 12.

When to Plant Soybeans in Lake County, MN

Lake County, Minnesota Zone 4a June

June to-do list for Lake County, Minnesota

June is a pivotal month for Lake County, Minnesota gardens. Focus on these tasks first and you'll set up the rest of the season for success.

Avg. last frost June 1
Avg. first frost September 12
Soil temp (4") 63°F
Watering Low
Pest pressure Moderate
Daylight 15.7 hrs
  1. Direct-sow soybeans

    Keep the top inch of soil moist until germination — a gentle morning watering for 5–7 days does the job.

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Soybeans (edamame) are a high-protein legume that fixes nitrogen in the soil. Fresh green soybeans harvested at the edamame stage are a nutritious snack.

Lake County, Minnesota is in USDA Zone 4a. The average last spring frost is June 1 and the first fall frost is September 12, giving you a growing season of approximately 103 days.

At an elevation of 1,191 feet, Lake County receives approximately 36.6 inches of rainfall annually with predominantly silt loam soil. Summer highs average 81°F, so choose short-season varieties of Soybeans to ensure they mature before fall.

Lake County, MN (Zone 4a) Short season
103 days
Last Spring Frost June 1
103 growing days
First Fall Frost September 12

Lake County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.8

Drainage

Well Drained

Soybeans Planting Risk Windows

Early Start (70% safe) ✗ May not fit
Transplant: May 20 🍅 Harvest: Aug 12 – Oct 7
Recommended (50%) ✗ May not fit
Transplant: Jun 1 🍅 Harvest: Aug 24 – Oct 19
Safe Start (90%) ✗ May not fit
Transplant: Jun 18 🍅 Harvest: Sep 10 – Nov 5

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 Lake County

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

Soil pH

Your soil pH (5.9–6.8) overlaps with Soybeans's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Soybeans.

Organic Matter

Organic matter is excellent (5.1%) — Soybeans will thrive.

How to Plant Soybeans

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

Soybeans Water Budget

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

Monthly Watering Guide for Soybeans

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

Month Soybeans Needs Rainfall You Supplement Action
Jan 1.4" 0" ❄️ Dormant
Feb 1.7" 0" ❄️ Dormant
Mar 2.7" 0" ❄️ Dormant
Apr 3.2" 0" ❄️ Dormant
May 4.6" 0" ❄️ Dormant
Jun 4.3" 5.2" 0" ✅ Rainfall sufficient
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 4.2" 0.1" 💧 Light watering
Sep 4.3" 3" 1.3" 💧 Light watering
Oct 2.4" 0" ❄️ Dormant
Nov 2.3" 0" ❄️ Dormant
Dec 2.1" 0" ❄️ Dormant

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

Soybeans 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.

Soybeans needs ~1,075 GDD — county provides 1,107 GDD Good fit

Soybeans Planting Timeline — Lake County, MN

Soybeans Planting Calendar

Activity When Date Range
Direct Sow June 15 Jun 15 – Jul 6
Harvest September 7 Sep 7 – Nov 2

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Natural rainfall sufficient

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 4a

📆 Growing Season

103 days in Lake County

Growing Tips for Soybeans in Lake County

Direct sow Soybeans outdoors after June 01 in Lake County when soil has warmed and frost danger has passed.

Your 103.0-day growing season in Lake County is tight for Soybeans (80.0-120.0 days to maturity). Start indoors and choose early-maturing varieties.

Common pests for Soybeans 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 soil warms to 60F. Plant in blocks rather than rows for better pollination. Harvest for edamame when pods are plump and bright green.

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 Soybeans in Lake County, MN?

Lake County is in Zone 4a with an average last frost of June 1. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Lake County, MN?

Lake County, Minnesota is in USDA Hardiness Zone 4a. The average last spring frost is June 1 and first fall frost is September 12.

When should I plant Soybeans in Lake County, MN?

In Lake County, MN, plant Soybeans after the last frost (around June 1) and before the first frost (around September 12). Best results when soil holds above 50°F.

What growing zone is Lake County, MN for Soybeans?

Lake County sits in USDA Zone 4a. Soybeans grows reliably in zones 3a through 10b, so it's a good fit here.

Can Soybeans grow in Lake County's climate?

Yes — Soybeans grows well in Lake County's temperate climate. Lake County averages a 103-day frost-free season, with last frost around June 1 and first frost around September 12.

🌱

Your Lake County Garden Planner — Free

A 22-page printable planner built for Lake County (Zone 4a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

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

Sources & credits

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