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When to plant Soybeans in Smith County, KS

Aim to plant Soybeans in Smith County on or after April 30; the window stays open through May 21. Smith County's 174-day frost-free season gives you a single solid spring crop with a brief fall option.

When to Plant Soybeans in Smith County, KS

Smith County, Kansas Zone 6a July

July in Smith County, Kansas — your action list

Each item below is timed to Smith County, Kansas's frost dates and soil temperatures. Skip nothing, stress about nothing.

Avg. last frost April 23
Avg. first frost October 14
Soil temp (4") 75°F
Watering Moderate
Pest pressure High
Daylight 14.6 hrs
  1. Bring in the soybeans

    The more you pick, the more the plant produces. Letting fruit overripen tells the plant it's time to stop.

Coming up in August — start thinking about
  • 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.

Smith County, Kansas is in USDA Zone 6a. The average last spring frost is April 23 and the first fall frost is October 14, giving you a growing season of approximately 174 days.

At an elevation of 1,048 feet, Smith County receives approximately 26.2 inches of rainfall annually with predominantly loam soil. Summer highs average 84°F, so choose short-season varieties of Soybeans to ensure they mature before fall.

Smith County, KS (Zone 6a) Moderate season
174 days
Last Spring Frost April 23
174 growing days
First Fall Frost October 14

Smith County Soil Profile

Soil Type

Loam

Soil pH

6.5-7.3

Drainage

Well Drained

Soybeans Planting Risk Windows

Early Start (70% safe) ✓ Fits season (36 days to spare)
Transplant: Apr 17 🍅 Harvest: Jul 10 – Sep 4
Recommended (50%) ✓ Fits season (34 days to spare)
Transplant: Apr 23 🍅 Harvest: Jul 16 – Sep 10
Safe Start (90%) ✓ Fits season (29 days to spare)
Transplant: May 10 🍅 Harvest: Aug 2 – Sep 27

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 Smith County

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

Soil pH

Your soil pH (6.5–7.3) overlaps with Soybeans's range (6.0–7.0), though not a perfect match.

Soil Texture

The loam soil in Smith 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 (3.4%). 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 174-day season

Sow every 9.1 weeks. Last sowing by Jun 16 to harvest before frost.

Soybeans Water Budget

Plant needs
1.0″/week
Rainfall provides
0.6″/week
You supply
0.8″/week
Watering frequency 2-3 times/week
Season total 1,241 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 0.7" 0" ❄️ Dormant
Feb 1" 0" ❄️ Dormant
Mar 1.7" 0" ❄️ Dormant
Apr 4.3" 2.6" 1.7" 💧 Light watering
May 4.3" 3.7" 0.6" 💧 Light watering
Jun 4.3" 4.1" 0.2" 💧 Light watering
Jul 4.3" 3" 1.3" 💧 Light watering
Aug 4.3" 3.4" 0.9" 💧 Light watering
Sep 4.3" 2.3" 2" 💧 Light watering
Oct 4.3" 1.9" 2.4" 🚿 Regular watering
Nov 1" 0" ❄️ Dormant
Dec 0.8" 0" ❄️ Dormant

Water needs are for active growing months only (Apr–Oct in Smith 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 ~1,300 GDD — county provides 2,262 GDD Excellent fit

Soybeans Planting Timeline — Smith County, KS

Soybeans Planting Calendar

Activity When Date Range
Direct Sow April 30 Apr 30 – May 21
Harvest July 23 Jul 23 – Sep 17

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 · 2-3 times/week

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: acceptable

🗺️ USDA Zone

Zone 6a

📆 Growing Season

174 days in Smith County

Growing Tips for Soybeans in Smith County

Direct sow Soybeans outdoors after April 23 in Smith 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 Smith County, KS?

Smith County is in Zone 6a with an average last frost of April 23. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Smith County, KS?

Smith County, Kansas is in USDA Hardiness Zone 6a. The average last spring frost is April 23 and first fall frost is October 14.

When should I plant Soybeans in Smith County, KS?

In Smith County, KS, plant Soybeans after the last frost (around April 23) and before the first frost (around October 14). Best results when soil holds above 50°F.

What growing zone is Smith County, KS for Soybeans?

Smith County sits in USDA Zone 6a. Soybeans grows reliably in zones 3a through 10b, so it's a good fit here.

Can Soybeans grow in Smith County's climate?

Yes — Soybeans grows well in Smith County's temperate climate. Smith County averages a 174-day frost-free season, with last frost around April 23 and first frost around October 14.

🌱

Your Smith County Garden Planner — Free

A 22-page printable planner built for Smith County (Zone 6a). 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 Smith County, KS. 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.