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When to Plant Edamame in Miller County, AR

Edamame are soybeans harvested at the immature green stage for a sweet, nutty snack. They are high in protein and easy to grow in warm climates.

Miller County, Arkansas is in USDA Zone 8a. The average last spring frost is March 21 and the first fall frost is November 12, giving you a growing season of approximately 236 days.

At an elevation of 266 feet, Miller County receives approximately 50.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93ยฐF, providing good warmth for Edamame during the growing season. Ample rainfall means less supplemental watering, but ensure good drainage to prevent Edamame root diseases.

Miller County, AR (Zone 8a) Long season
236 days
Last Spring Frost March 21
236 growing days
First Fall Frost November 12

Miller County Soil Profile

Soil Type

Silt Loam

Soil pH

5.3-7.1

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (114 days to spare)
Transplant: Mar 12 🍅 Harvest: May 28 – Jul 9
Recommended (50%) ✓ Fits season (117 days to spare)
Transplant: Mar 21 🍅 Harvest: Jun 6 – Jul 18
Safe Start (90%) ✓ Fits season (110 days to spare)
Transplant: Apr 14 🍅 Harvest: Jun 30 – Aug 11

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 Miller County

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

Soil pH

Your soil pH (5.3โ€“7.1) overlaps with Edamame's range (6.0โ€“7.0), though not a perfect match.

Soil Texture

The silt loam soil in Miller County is excellent for Edamame โ€” good drainage, moisture retention, and nutrient holding capacity.

Organic Matter

Organic matter is moderate (3.2%). Annual compost additions will help Edamame.

How to Plant Edamame

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

Succession Planting Edamame

3
successive plantings in your 236-day season

Sow every 8.6 weeks. Last sowing by Aug 04 to harvest before frost.

Plant Water Budget

Plant needs
0.9″/week
Rainfall provides
0.9″/week
Watering frequency Only during dry spells
Season total 8 gal / 100 sq ft
Drought risk

Water stress score is 6/10 โ€” consider drought-tolerant varieties and mulching

Monthly Watering Guide for Edamame

Edamame needs approximately 0.9 inches of water per week (3.9" per month). Here's how your county's rainfall compares month by month.

Month Edamame Needs Rainfall You Supplement Action
Jan โ€” 3.7" 0" โ„๏ธ Dormant
Feb โ€” 3.3" 0" โ„๏ธ Dormant
Mar 3.9" 5" 0" โœ… Rainfall sufficient
Apr 3.9" 3.9" 0" โœ… Rainfall sufficient
May 3.9" 4" 0" โœ… Rainfall sufficient
Jun 3.9" 4.6" 0" โœ… Rainfall sufficient
Jul 3.9" 5.7" 0" โœ… Rainfall sufficient
Aug 3.9" 5.1" 0" โœ… Rainfall sufficient
Sep 3.9" 4.1" 0" โœ… Rainfall sufficient
Oct 3.9" 3.4" 0.5" ๐Ÿ’ง Light watering
Nov 3.9" 4.1" 0" โœ… Rainfall sufficient
Dec โ€” 3.5" 0" โ„๏ธ Dormant

Water needs are for active growing months only (Marโ€“Nov in Miller County). Supplement amounts are based on average rainfall โ€” actual needs vary with temperature, soil, and mulching.

Edamame 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" โ€” every day above 50ยฐF 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.

Edamame needs ~1,728 GDD — county provides 4,661 GDD Excellent fit

Edamame Planting Timeline โ€” Miller County, AR

Edamame Planting Calendar

Activity When Date Range
Direct Sow March 28 Mar 28 โ€“ Apr 18
Harvest June 13 Jun 13 โ€“ Jul 25

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

Month-by-Month Timeline

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

Growing Conditions

โ˜€๏ธ Sun

Full Sun (6-8+ hours)

๐Ÿ’ง Water

0.9"/week ยท Only during dry spells

๐Ÿ“… Days to Maturity

75โ€“100 days

๐Ÿงช Soil pH

Needs 6โ€“7 ยท Your soil: acceptable

๐Ÿ—บ๏ธ USDA Zone

Zone 8a

๐Ÿ“† Growing Season

236 days in Miller County

Growing Tips for Edamame in Miller County

Direct sow Edamame outdoors after March 21 in Miller County when soil has warmed and frost danger has passed.

Common pests for Edamame 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 is warm. Do not over-fertilize with nitrogen. Harvest when pods are plump and bright green but before they start to yellow. Steam or boil pods before eating.

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 Edamame in Miller County, AR?

Miller County is in Zone 8a with an average last frost of March 21. Plan your Edamame planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Miller County, AR?

Miller County, Arkansas is in USDA Hardiness Zone 8a. The average last spring frost is March 21 and first fall frost is November 12.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Miller County gardeners in Zone 8a organize planting dates, track what's growing, and never miss a planting window.

Get Your Free Garden Planner →

Free download. Plan your entire garden season in minutes.

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