When to Plant Soybeans in Union County, NJ
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.
Union County, New Jersey is in USDA Zone 7a. The average last spring frost is March 29 and the first fall frost is November 12, giving you a growing season of approximately 228 days.
At an elevation of 814 feet, Union County receives approximately 49.4 inches of rainfall annually with predominantly silt loam soil. Summer highs average 93°F, providing good warmth for Soybeans during the growing season.
Union County Soil Profile
Soil Type
Silt Loam
Soil pH
4.8-6.5
Drainage
Well Drained
Plant Planting Risk Windows
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
Soybeans Planting Timeline — Union County, NJ
Soybeans Planting Calendar
| Activity | When | Date Range |
|---|---|---|
| Direct Sow | April 5 | Apr 5 – Apr 26 |
| Harvest | June 28 | Jun 28 – Aug 23 |
Plant 1" deep · 15" apart · Rows 24" apart
Month-by-Month Timeline
| Month | Activities |
|---|---|
| January | — |
| February | — |
| March | — |
| 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
6 – 7
USDA Zone
Zone 7a
Growing Season
228 days
Growing Tips for Union 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
Level Up Your Garden
Soybeans in Other Locations
Frequently Asked Questions
When should I plant Soybeans in Union County, NJ?
Union County is in Zone 7a with an average last frost of March 29. Plan your Soybeans planting based on this frost date — see the calendar above for exact timing.
What planting zone is Union County, NJ?
Union County, New Jersey is in USDA Hardiness Zone 7a. The average last spring frost is March 29 and first fall frost is November 12.
Plan Your Garden with Confidence
Get our free Garden Planner — designed to help Union County gardeners in Zone 7a organize planting dates, track what's growing, and never miss a planting window.
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