Edamame

Thrives in USDA Zones 3 - 10

• Direct Sow

  After last frost, soil 65°F+

• Harvest

  75 - 90 days; harvest when pods are plump and bright green before they yellow

• Inoculate seed with Bradyrhizobium japonicum at planting to ensure nitrogen fixation.

• Plant in blocks rather than rows to improve pollination and pod set.

• Harvest the entire plant at once when 80% of pods are plump - flavor peaks briefly.

• After harvest, chop plants and till them in to return fixed nitrogen to the soil.

• Watering

  If the top 2 inches of soil feel dry, a deep watering at the base may help more than frequent light watering. In healthy soil, rain may cover much of what it needs.

• Feeding

  Extra feeding is rarely required if soil is healthy. If growth looks pale or slow, a light compost top-dressing is often enough before adding anything stronger.

• Seasonal care

  During the main season, harvesting when the crop is ready and removing damaged growth can help keep the planting productive if it starts to look crowded or tired.

• Envy

  Early 75-day variety with excellent flavor and reliable production; well-suited for short seasons.

  Best for

  short seasons, beginners

• Midori Giant

  Large-podded variety with 3 beans per pod and outstanding flavor; 80 days.

  Best for

  flavor, farmers markets

• Butterbeans

  Sweet, creamy edamame with larger beans and a buttery flavor; 85 days.

  Best for

  fresh eating, summer harvest

• Beer Friend

  Japanese specialty variety with exceptional sweetness; developed specifically for fresh eating.

  Best for

  gourmet use, fresh snacking

• Mexican Bean Beetle
• Aphids
• Spider Mites
• Japanese Beetle
• Corn Earworm

Origin

Domesticated in northeastern China from wild soybean (Glycine soja).

Native Habitat

The wild ancestor Glycine soja grows in thickets, forest margins, and disturbed ground in northeastern Asia.

Current Distribution

Cultivated globally as one of the world's most important crop plants; grown in over 100 countries.

Kingdom

Plantae

Family

Legume family (Fabaceae)

Genus

Glycine

Species

max

• Root System

  Fibrous, moderately deep roots with rhizobial nitrogen-fixing nodules when appropriate soil bacteria are present.

• Stem

  Erect, hairy, bushy stems 18 - 30 inches tall; self-supporting; branching habit produces multiple pod-bearing nodes.

• Leaves

  Trifoliate leaves similar to common beans; alternate; hairy on both surfaces; medium to dark green.

• Flowers

  Small, inconspicuous pinkish-white or purple self-pollinating flowers held in clusters at leaf axils.

• Fruit

  Fuzzy green pods 2 - 3 inches long with 2 - 3 seeds each; harvest at full green plumpness before yellowing begins.

Glycine max was domesticated from wild soybean (Glycine soja) in northeastern China approximately 3,000 years ago, though archaeological evidence suggests cultivation as early as 5,000 BCE in the Yellow River basin. The Shennong Bencao Jing, a foundational Chinese agricultural text, lists soybeans among the five sacred grains of Chinese civilization alongside rice, wheat, millet, and hemp. For most of its long history the plant was grown for dry beans, fermented products such as miso and tofu, and oil extraction. The edamame tradition - eating fresh green soybeans - developed within Japanese cuisine, with the earliest clear references appearing in Japanese texts from the 17th century. Japanese farmers developed specific edamame varieties selected for sweetness and tenderness. Benjamin Franklin is often credited with sending the first soybean seeds to the American Philosophical Society from Paris in 1770. The US is now the world's largest soybean producer, though virtually all of that production is for oil, meal, and processed food ingredients rather than edamame.