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When to Plant Soybeans in USDA Zone 5a

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.

In Zone 5a, the average last spring frost is around April 25 and the first fall frost is around October 8, giving you a growing season of approximately 166 days.

Zone 5a Moderate season
166 days
Last Spring Frost April 25
166 growing days
First Fall Frost October 8

Soybeans Planting Timeline — Zone 5a

Where Is USDA Zone 5a?

The map below highlights the states that contain Zone 5a. Click any state to see the Soybeans planting schedule for that location.

Prints a clean, ink-friendly version without maps or navigation.

Soybeans Planting Calendar — Zone 5a

Activity When Date Range
Direct Sow May 2 May 2 – May 23
Harvest July 25 Jul 25 – Sep 19

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

Month-by-Month Timeline

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

Free Zone 5a Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 5a with start dates, transplant windows, and harvest times.

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Growing Conditions

Sun

Full Sun (6-8+ hours)

💧 Water

Moderate — regular watering

Days to Maturity

80–120 days

Soil pH

6 – 7

Zone Temperature Range

-20°F to -15°F average annual minimum

Growing Season

166 days (Zone 5a average)

Planting Specifications

Planting Depth1 inches
Plant Spacing15 inches apart
Row Spacing24 inches between rows

Succession Planting Soybeans in Zone 5a

2
successive plantings in Zone 5a's ~166-day season

Sow every 9.1 weeks for continuous harvest throughout the season.

Growing Tips for Soybeans in Zone 5a

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

Level Up Your Garden

Saving Soybeans Seeds

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Seed Starting Trays $8-20

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Soil Test Kit $12-25

Test your soil pH, nitrogen, phosphorus, and potassium levels before planting.

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Garden Plant Markers $6-12

Keep your garden organized with durable, weather-resistant plant labels.

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Frequently Asked Questions

When should I plant Soybeans in Zone 5a?

In Zone 5a, plan your Soybeans planting around the average last frost date of April 25. Direct sow outdoors around May 2.

Can Soybeans grow in Zone 5a?

Yes, Soybeans can grow well in Zone 5a, hardy in USDA zones 3a through 10b. Zone 5a has a growing season of approximately 166 days, which is sufficient for Soybeans (80-120 days to maturity).

When can I harvest Soybeans in Zone 5a?

In Zone 5a, expect to harvest Soybeans from July 25 – September 19. Soybeans takes 80-120 days from planting to harvest.

What is the last frost date for Zone 5a?

The average last spring frost in Zone 5a is around April 25, and the first fall frost is around October 8. This gives a growing season of approximately 166 days. These are 50% probability dates — actual frost dates vary year to year.

What should I plant next to Soybeans?

Good companion plants for Soybeans include Corn, Squash Summer, Potatoes. These companions can help with pest control, pollination, and nutrient sharing.

🌱

Plan Your Garden with Confidence

Get our free Garden Planner — organize your planting dates for Zone 5a, track your crops, and plan your garden season from seed to harvest.

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Free download. Plan your entire garden season in minutes.

Data sources: USDA Plant Hardiness Zone Map (2023), NOAA 30-Year Climate Normals, University Cooperative Extension planting guides. Planting dates are estimates based on average frost dates — local conditions may vary. Last updated: April 2026.