How to grow edamame (soybean)
Glycine max · Fabaceae · Vegetable
When to plant edamame (soybean): the short answer
Sow outdoors about 1 week after the last frost. Wait until the soil is at least 60°F; edamame (soybean) sprout fastest near 77°F.
Zone 5: sow May 2 – May 21. Zone 7: sow Apr 7 – Apr 26. Zone 9: sow Feb 22 – Mar 13. See every zone.
Edamame (Soybean) is a warm-season vegetable in the Fabaceae family, almost always sown straight into the ground where it will grow. It wants full sun (six or more hours of direct light) and steady, even moisture. From sowing to first pick is about 75–100 days. It is killed by frost, so nothing goes outside until the danger has passed and the soil has warmed.
Grower’s note: Vegetable soybeans, picked young when the pods are plump and bright green. The whole plant tends to mature at once, so sow two or three times. Boil pods 5 minutes in salted water and pop the beans out.
Sowing
Sow about 1.3″ deep, into soil between 60–95°F — germination is quickest near 77°F. It comes up fast (5–10 days). It does not transplant well, so sow it in its final position rather than starting it in pots.
Spacing & layout
Give each plant about 4″ along the row with roughly 24″ between rows. On a square-foot grid that is 4 per square foot. Allow at least 18″ of loose, workable soil for the roots. It grows well in containers at least 12″ deep.
Fitting it to your season
Edamame (Soybean) needs roughly 75–100 frost-free days to crop. Where the season is shorter than that, start it indoors and choose the earliest-maturing varieties, or grow it in a container you can move under cover on cold nights. In long, hot-summer regions it can often be planted twice — once in spring and again in mid-to-late summer for a fall harvest.
Quick facts
Growth stages: how long edamame (soybean) takes to grow
From sowing to first harvest takes roughly 75-100 days (11-14 weeks), with seedlings appearing after 5-10 days in soil around 77°F.
When to plant edamame (soybean)
When to plant edamame (soybean) by USDA zone
Dates worked out from each zone’s typical frost dates for 2026. Find your zone on the zone map, or pick your state below for dates from its own frost dates. Zones 11 and above are frost-free, so timing there depends on heat and rain instead.
| Zone | Last / first frost | Start indoors | Sow or plant out |
|---|---|---|---|
| Zone 3 | May 15 / Sep 15 | - | May 17 – Jun 5 |
| Zone 4 | May 10 / Sep 25 | - | May 12 – May 31 |
| Zone 5 | Apr 30 / Oct 5 | - | May 2 – May 21 |
| Zone 6 | Apr 15 / Oct 15 | - | Apr 17 – May 6 |
| Zone 7 | Apr 5 / Oct 25 | - | Apr 7 – Apr 26 |
| Zone 8 | Mar 20 / Nov 5 | - | Mar 22 – Apr 10 |
| Zone 9 | Feb 20 / Nov 30 | - | Feb 22 – Mar 13 |
| Zone 10 | Jan 30 / Dec 15 | - | Feb 1 – Feb 20 |
Companions
Cucumber, Sweet Corn, Potato
Onion, Garlic
Common problems
Pests: bean leaf beetle, Japanese beetle, stink bug.
Diseases & disorders: bacterial blight, downy mildew, soybean mosaic virus.
Same family (Fabaceae)
Rotate these so they don’t follow each other in the same bed year to year.
Questions gardeners ask
When should I plant edamame (soybean)?
Sow outdoors about 1 week after the last frost. Wait until the soil is at least 60°F. The table on this page gives dates for each USDA zone, and the planting calendar gives dates for your own state or ZIP code.
How long does edamame (soybean) take to grow?
About 75-100 days from sowing to the first harvest. Seeds germinate in 5-10 days, fastest in soil around 77°F.
How much sun does edamame (soybean) need?
It needs at least six to eight hours of direct sun a day.
What soil pH does edamame (soybean) need?
A soil pH between 6.0 and 7.0. Test before adding lime or sulfur - see the soil pH and testing guide.
How far apart should I plant edamame (soybean)?
Space plants about 4 inches apart in rows 24 inches apart, or 4 per square foot in a square-foot bed. Sow seeds about 1.25 inches deep.
Can I grow edamame (soybean) in a container?
Yes. Use a container at least 12 inches deep with drainage holes and a good potting mix, and water more often than you would in the ground.
Figures are typical home-garden ranges from Cooperative Extension planting guides, cross-checked against multiple state sources. Your variety and conditions will vary.