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When to Plant Soybeans in Carroll County, TN

Carroll County, Tennessee Zone 7b May

Top priorities for Carroll County, Tennessee gardeners in May

We've pulled the most time-sensitive tasks for Carroll County, Tennessee this May and put them front and centre. Tackle them in order.

Avg. last frost April 4
Avg. first frost October 27
Soil temp (4") 60°F
Watering Moderate
Pest pressure Moderate
Daylight 13.9 hrs

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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.

Carroll County, Tennessee is in USDA Zone 7b. The average last spring frost is April 4 and the first fall frost is October 27, giving you a growing season of approximately 206 days.

At an elevation of 2,921 feet, Carroll County receives approximately 40.3 inches of rainfall annually with predominantly silt loam soil. Summer highs average 89°F, providing good warmth for Soybeans during the growing season.

Carroll County, TN (Zone 7b) Long season
206 days
Last Spring Frost April 4
206 growing days
First Fall Frost October 27
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Carroll County Soil Profile

Soil Type

Silt Loam

Soil pH

5.5-6.5

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (68 days to spare)
Transplant: Mar 27 🍅 Harvest: Jun 19 – Aug 14
Recommended (50%) ✓ Fits season (66 days to spare)
Transplant: Apr 4 🍅 Harvest: Jun 27 – Aug 22
Safe Start (90%) ✓ Fits season (68 days to spare)
Transplant: Apr 19 🍅 Harvest: Jul 12 – Sep 6

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 Carroll County

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

Soil pH

Your soil pH (5.5–6.5) overlaps with Soybeans's range (6.0–7.0), though not a perfect match.

Soil Texture

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

Organic Matter

Organic matter is moderate (3.1%). 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 206-day season

Sow every 9.1 weeks. Last sowing by Jun 29 to harvest before frost.

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 327 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 3.4" 0" ❄️ Dormant
Feb 3.1" 0" ❄️ Dormant
Mar 3.4" 0" ❄️ Dormant
Apr 4.3" 3.3" 1" 💧 Light watering
May 4.3" 2.9" 1.4" 💧 Light watering
Jun 4.3" 3.9" 0.4" 💧 Light watering
Jul 4.3" 3.9" 0.4" 💧 Light watering
Aug 4.3" 4.4" 0" ✅ Rainfall sufficient
Sep 4.3" 2.7" 1.6" 💧 Light watering
Oct 4.3" 2.9" 1.4" 💧 Light watering
Nov 3" 0" ❄️ Dormant
Dec 3.4" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Carroll 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 ~1,675 GDD — county provides 3,450 GDD Excellent fit

Soybeans Planting Timeline — Carroll County, TN

Soybeans Planting Calendar

Activity When Date Range
Direct Sow April 11 Apr 11 – May 2
Harvest July 4 Jul 4 – Aug 29

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
October
November
December
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Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

1"/week · Only during dry spells

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 7b

📆 Growing Season

206 days in Carroll County

Growing Tips for Soybeans in Carroll County

Direct sow Soybeans outdoors after April 04 in Carroll 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 Carroll County, TN?

Carroll County is in Zone 7b with an average last frost of April 4. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Carroll County, TN?

Carroll County, Tennessee is in USDA Hardiness Zone 7b. The average last spring frost is April 4 and first fall frost is October 27.

🌱

Your Carroll County Garden Planner — Free

A 24-page printable planner built for Carroll County (Zone 7b). 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 Carroll County, TN. Local conditions may vary. Last updated: May 2026.

Sources & credits

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