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When to Plant Soybeans in Chester County, PA

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.

Chester County, Pennsylvania is in USDA Zone 6b. The average last spring frost is April 16 and the first fall frost is October 27, giving you a growing season of approximately 194 days.

At an elevation of 761 feet, Chester County receives approximately 42.7 inches of rainfall annually with predominantly silt loam soil. Summer highs average 86ยฐF, providing good warmth for Soybeans during the growing season.

Chester County, PA (Zone 6b) Moderate season
194 days
Last Spring Frost April 16
194 growing days
First Fall Frost October 27

Chester County Soil Profile

Soil Type

Silt Loam

Soil pH

4.9-6.6

Drainage

Well Drained

Plant Planting Risk Windows

Early Start (70% safe) ✓ Fits season (51 days to spare)
Transplant: Apr 10 🍅 Harvest: Jul 3 – Aug 28
Recommended (50%) ✓ Fits season (54 days to spare)
Transplant: Apr 16 🍅 Harvest: Jul 9 – Sep 3
Safe Start (90%) ✓ Fits season (43 days to spare)
Transplant: May 5 🍅 Harvest: Jul 28 – Sep 22

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.

Plant Water Budget

Plant needs
1.0″/week
Rainfall provides
0.9″/week
You supply
0.1″/week
Watering frequency Only during dry spells
Season total 130 gal / 100 sq ft
Soybeans needs ~1,450 GDD — county provides 2,813 GDD Excellent fit

Soybeans Planting Timeline โ€” Chester County, PA

Soybeans Planting Calendar

Activity When Date Range
Direct Sow April 23 Apr 23 โ€“ May 14
Harvest July 16 Jul 16 โ€“ Sep 10

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

Month-by-Month Timeline

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

Growing Conditions

Sun

Full Sun (6-8+ hours)

Water

Moderate โ€” regular watering

Days to Maturity

80โ€“120 days

Soil pH

6 โ€“ 7

USDA Zone

Zone 6b

Growing Season

194 days

Growing Tips for Chester 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

Level Up Your Garden

Frequently Asked Questions

When should I plant Soybeans in Chester County, PA?

Chester County is in Zone 6b with an average last frost of April 16. Plan your Soybeans planting based on this frost date โ€” see the calendar above for exact timing.

What planting zone is Chester County, PA?

Chester County, Pennsylvania is in USDA Hardiness Zone 6b. The average last spring frost is April 16 and first fall frost is October 27.

๐ŸŒฑ

Plan Your Garden with Confidence

Get our free Garden Planner โ€” designed to help Chester County gardeners in Zone 6b organize planting dates, track what's growing, and never miss a planting window.

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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 Chester County, PA. Local conditions may vary. Last updated: April 2026.