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When to plant Soybeans in Clark County, AR

Clark County's spring Soybeans window runs March 29 through April 19. most warm-season crops establish quickly once soil holds above 60°F.

When to Plant Soybeans in Clark County, AR

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.

Clark County, Arkansas is in USDA Zone 8a. The average last spring frost is March 22 and the first fall frost is November 9, giving you a growing season of approximately 232 days.

At an elevation of 1,350 feet, Clark County receives approximately 45.2 inches of rainfall annually with predominantly silt loam soil. Summer highs average 91°F, providing good warmth for Soybeans during the growing season.

Clark County, AR (Zone 8a) Long season
232 days
Last Spring Frost March 22
232 growing days
First Fall Frost November 9

Clark County Soil Profile

Soil Type

Silt Loam

Soil pH

5.7-6.7

Drainage

Well Drained

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 4.2" 0" ❄️ Dormant
Feb 3.6" 0" ❄️ Dormant
Mar 4.3" 3.6" 0.7" 💧 Light watering
Apr 4.3" 3.8" 0.5" 💧 Light watering
May 4.3" 3.3" 1" 💧 Light watering
Jun 4.3" 3.9" 0.4" 💧 Light watering
Jul 4.3" 5.1" 0" ✅ Rainfall sufficient
Aug 4.3" 4" 0.3" 💧 Light watering
Sep 4.3" 3.7" 0.6" 💧 Light watering
Oct 4.3" 2.5" 1.8" 💧 Light watering
Nov 4.3" 3.5" 0.8" 💧 Light watering
Dec 3.9" 0" ❄️ Dormant

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

Soybeans Planting Timeline — Clark County, AR

Soybeans Planting Calendar

Activity When Date Range
Direct Sow March 29 Mar 29 – Apr 19
Harvest June 21 Jun 21 – Aug 16

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

Month-by-Month Timeline

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

Growing Conditions

☀️ Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

📅 Days to Maturity

80–120 days

🧪 Soil pH

Needs 6–7 · Your soil: N/A

🗺️ USDA Zone

Zone 8a

📆 Growing Season

232 days in Clark County

Growing Tips for Clark County

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 Clark County, AR?

Clark County is in Zone 8a with an average last frost of March 22. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.

What planting zone is Clark County, AR?

Clark County, Arkansas is in USDA Hardiness Zone 8a. The average last spring frost is March 22 and first fall frost is November 9.

When should I plant Soybeans in Clark County, AR?

In Clark County, AR, plant Soybeans after the last frost (around March 22) and before the first frost (around November 9). Best results when soil holds above 50°F.

What growing zone is Clark County, AR for Soybeans?

Clark County sits in USDA Zone 8a. Soybeans grows reliably in zones 3a through 10b, so it's a good fit here.

Can Soybeans grow in Clark County's climate?

Yes — Soybeans grows well in Clark County's temperate climate. Clark County averages a 232-day frost-free season, with last frost around March 22 and first frost around November 9.

🌱

Your Clark County Garden Planner — Free

A 22-page printable planner built for Clark County (Zone 8a). Planting dates, a month-by-month schedule, harvest log, seed inventory, and succession charts — all dialed in for your exact growing season.

Instant PDF download. No spam, unsubscribe any time.

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

Sources & credits

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