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When to plant Soybeans in Cedar County, IA

Plant Soybeans in Cedar County from April 24 to May 15 in spring. Cedar County sits in USDA Zone 5a, with last frost around April 17 and first frost on October 16.

When to Plant Soybeans in Cedar County, IA

Cedar County, Iowa Zone 5a July

July in Cedar County, Iowa — your action list

Your garden in Cedar County, Iowa is working on a schedule, even when you're not. Here's where you should be this July.

Avg. last frost April 17
Avg. first frost October 16
Soil temp (4") 78°F
Watering Low
Pest pressure High
Daylight 14.7 hrs
  1. Harvest soybeans as they ripen

    Don't tug. Use scissors or pruners for clean cuts — torn stems invite disease.

To set up a strong August, finish these tasks
  • First harvests: soybeans

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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.

Cedar County, Iowa is in USDA Zone 5a. The average last spring frost is April 17 and the first fall frost is October 16, giving you a growing season of approximately 182 days.

At an elevation of 1,112 feet, Cedar County receives approximately 41 inches of rainfall annually with predominantly silt loam soil. Summer highs average 87°F, providing good warmth for Soybeans during the growing season.

Cedar County, IA (Zone 5a) Moderate season
182 days
Last Spring Frost April 17
182 growing days
First Fall Frost October 16

Cedar County Soil Profile

Soil Type

Silt Loam

Soil pH

5.9-6.9

Drainage

Well Drained

Soybeans Planting Risk Windows

Early Start (70% safe) ✓ Fits season (40 days to spare)
Transplant: Apr 12 🍅 Harvest: Jul 5 – Aug 30
Recommended (50%) ✓ Fits season (42 days to spare)
Transplant: Apr 17 🍅 Harvest: Jul 10 – Sep 4
Safe Start (90%) ✓ Fits season (38 days to spare)
Transplant: May 8 🍅 Harvest: Jul 31 – Sep 25

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 Cedar County

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

Soil pH

Your soil pH (5.9–6.9) overlaps with Soybeans's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Drainage

Drainage is adequate for Soybeans.

Organic Matter

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

How to Plant Soybeans

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

Succession Planting Soybeans

2
successive plantings in your 182-day season

Sow every 9.1 weeks. Last sowing by Jun 18 to harvest before frost.

Soybeans Water Budget

Plant needs
1.0″/week
Rainfall provides
1.0″/week
You supply
0.4″/week
Watering frequency 1-2 times/week
Season total 688 gal / 100 sq ft
Drought risk

Water stress score is 6/10 — consider drought-tolerant varieties and mulching

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 1.6" 0" ❄️ Dormant
Feb 1.5" 0" ❄️ Dormant
Mar 2.8" 0" ❄️ Dormant
Apr 4.3" 3.4" 0.9" 💧 Light watering
May 4.3" 5.1" 0" ✅ Rainfall sufficient
Jun 4.3" 5.3" 0" ✅ Rainfall sufficient
Jul 4.3" 4.9" 0" ✅ Rainfall sufficient
Aug 4.3" 4.7" 0" ✅ Rainfall sufficient
Sep 4.3" 3.5" 0.8" 💧 Light watering
Oct 4.3" 3.2" 1.1" 💧 Light watering
Nov 3" 0" ❄️ Dormant
Dec 2" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Cedar 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 ~1,525 GDD — county provides 2,775 GDD Excellent fit

Soybeans Planting Timeline — Cedar County, IA

Soybeans Planting Calendar

Activity When Date Range
Direct Sow April 24 Apr 24 – May 15
Harvest July 17 Jul 17 – Sep 11

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · 1-2 times/week

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 5a

📆 Growing Season

182 days in Cedar County

Growing Tips for Soybeans in Cedar County

Direct sow Soybeans outdoors after April 17 in Cedar County when soil has warmed and frost danger has passed.

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 Cedar County, IA?

Cedar County is in Zone 5a with an average last frost of April 17. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Cedar County, IA?

Cedar County, Iowa is in USDA Hardiness Zone 5a. The average last spring frost is April 17 and first fall frost is October 16.

When should I plant Soybeans in Cedar County, IA?

In Cedar County, IA, plant Soybeans after the last frost (around April 17) and before the first frost (around October 16). Best results when soil holds above 50°F.

What growing zone is Cedar County, IA for Soybeans?

Cedar County sits in USDA Zone 5a. Soybeans grows reliably in zones 3a through 10b, so it's a good fit here.

Can Soybeans grow in Cedar County's climate?

Yes — Soybeans grows well in Cedar County's temperate climate. Cedar County averages a 182-day frost-free season, with last frost around April 17 and first frost around October 16.

🌱

Your Cedar County Garden Planner — Free

A 22-page printable planner built for Cedar County (Zone 5a). 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 Cedar County, IA. Local conditions may vary. Last updated: July 2026.

Sources & credits

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