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When to Plant Soybeans in USDA Zone 10b

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 10b, the average last spring frost is around January 1 and the first fall frost is around December 31, giving you a growing season of approximately 364 days.

Zone 10b Year-round
364 days
Last Spring Frost January 1
364 growing days
First Fall Frost December 31

Soybeans Planting Timeline — Zone 10b

Where Is USDA Zone 10b?

The map below highlights the states that contain Zone 10b. 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 10b

Activity When Date Range
Direct Sow January 8 Jan 8 – Jan 29
Harvest April 2 Apr 2 – May 28

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

Month-by-Month Timeline

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

Free Zone 10b Planting Calendar PDF

Know exactly when to plant every crop in your zone. Get a printable month-by-month calendar customized for Zone 10b 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

35°F to 40°F average annual minimum

Growing Season

364 days (Zone 10b average)

Planting Specifications

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

Growing Tips for Zone 10b

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

Recommended for Your Garden

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Garden Shade Cloth $15-35

Reduce heat stress and sun scorch in hot climates with UV-stabilized shade cloth.

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Seed Starting Trays $8-20

Start seeds indoors with reusable cell trays and humidity domes.

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Soil Test Kit $12-25

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

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Frequently Asked Questions

When should I plant Soybeans in Zone 10b?

In Zone 10b, plan your Soybeans planting around the average last frost date of January 1. Direct sow outdoors around January 8.

Can Soybeans grow in Zone 10b?

Yes, Soybeans can grow well in Zone 10b, hardy in USDA zones 3a through 10b. Zone 10b has a growing season of approximately 364 days, which is sufficient for Soybeans (80-120 days to maturity).

When can I harvest Soybeans in Zone 10b?

In Zone 10b, expect to harvest Soybeans from April 2 – May 28. Soybeans takes 80-120 days from planting to harvest.

What is the last frost date for Zone 10b?

The average last spring frost in Zone 10b is around January 1, and the first fall frost is around December 31. This gives a growing season of approximately 364 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 10b, track your crops, and plan your garden season from seed to harvest.

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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.