When to plant edamame in USDA zone 6

Key dates for edamame in zone 6

Dates are zone-wide averages. Local microclimates (south-facing slopes, urban heat, lakeside warmth, elevation) can shift the planting window by 1-2 weeks within the same zone.

Why this timing works for zone 6

Zone 6 has average annual minimum temperatures of -10 to 0°F and a 180-day frost-free window from mid- to late April to mid- to late October. Edamame are tender — they need soil above 16 °C to grow and stop fruiting once nights drop below 10 °C. That puts the safe outdoor planting window after the last spring frost passes, and the harvest closes when fall temperatures arrive.

Direct sow after last frost when soil is at least 60 °F (16 °C); seeds rot readily in cold, wet soil. Harvest at the edamame (green-pod) stage 75–90 days from sowing, when pods are plump and bright green — the window is only 5–7 days before beans mature to dry soybeans. Zones 3–4 should select fast-maturing varieties (≤80 days) and use black plastic mulch to warm soil; zones 9–11 can make a second sowing in late summer for fall harvest.

Quick-grow guide

• Sun: Full sun — 6+ hours direct.
• Soil temperature for germination: 16–35 °C (60–95 °F); optimal 21–32 °C (70–90 °F).
• Spacing: 6 inches (15 cm) plants; 18–24 inches (45–60 cm) between rows between plants.
• Days to harvest from direct sow: ~80 days.
• Wait until night temperatures stay above 10 °C — cold soil stunts warm-season crops permanently.

Common mistakes — zone 6 × edamame

• Planting before last frost: zone 6's last frost averages mid- to late April, and even a light frost will kill edamame seedlings overnight.
• Skipping hardening off: even healthy indoor transplants need 7-10 days of progressive outdoor exposure before going in the ground.

Source and methodology

Frost-date averages from NOAA Climate Data Online within each USDA hardiness zone. Hardiness zone boundaries from the USDA Plant Hardiness Zone Map (2023). Crop timing offsets calibrated against US Cooperative Extension Service publications (UNL, UMN, NC State, Texas A&M, UF/IFAS) and cross-checked against the RHS sowing calendar for en-GB readers. Curated by the Growli editorial team.

Keep going

• How to grow edamame — full guide
• USDA Zone 6 — frost dates and what else to plant
• All 13 USDA hardiness zones

Same crop, nearby zones

• When to plant edamame in USDA zone 5
• When to plant edamame in USDA zone 7
• When to plant edamame in USDA zone 8

Other crops for zone 6

• When to plant tomatoes in zone 6
• When to plant peppers in zone 6
• When to plant basil in zone 6
• When to plant garlic in zone 6
• When to plant lettuce in zone 6
• When to plant bush beans in zone 6