Grain · Fabaceae
When to plant soybeans
Picked green as edamame at around 85 days or left to dry down for storage. Day length as much as temperature decides when it flowers.
Sow direct
2 weeks after
Counted from your last spring frost.
Days to maturity
85-120
From sowing to a first picking.
Frost tolerance
Tender
How much cold the plant itself will take.
Those weeks become real dates once you name a place.
Timing, in frost-relative terms
Seed packets rarely give calendar dates, because a date that suits one latitude is wrong at another. They give offsets from the last spring frost instead, and those offsets are what make soybeans plantable anywhere.
- Sow direct 2 weeks after the last frost.
- Expect 85–120 days to maturity, counted from sowing.
Getting the timing right
Sow two weeks after the last frost into warm soil. Varieties are grouped by maturity for a given latitude, and a variety from the wrong group will either flower far too early or fail to finish at all - this matters more with soybeans than with almost any other crop.
Frost tolerance
No frost tolerance. Killed at 0C at both ends of the season.
Classified as tender, with damage expected below 0°C (32°F)32°F (0°C).