How to Grow Amsoy Soybean

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Amsoy Soybean

Glycine max 'Amsoy'

vegetable

Amsoy is a determinate soybean cultivar bred for high yields and reliable performance in temperate climates. It produces compact plants with prolific pod development and is commonly grown for grain, animal feed, and edamame purposes. This variety is valued for its disease resistance and adaptability to diverse growing conditions.

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Example Amsoy Soybean timeline · Pittsburgh, PA (Zone 6b)

  1. Plant Amsoy Soybean

    Around Apr 17

    Near Pittsburgh's average last spring frost.

  2. Tend & protect

    Late spring–summer

    Watering, feeding, and pest-watch reminders.

  3. Harvest Amsoy Soybean

    Around Jul 26

    ≈ 100 days after planting

Sample dates for Pittsburgh, PA. Sign up to get exact Amsoy Soybean dates for your own zip code.

Growing Conditions

☀️
Sun: Full sun, 6-8 hours daily minimum; 8+ hours preferred for optimal growth
💧
Water: Moderate water needs; require 1-1.5 inches per week, especially during flowering and pod development. Consistent moisture is important but avoid waterlogging. Drought tolerant once established.
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Spacing: 4 inches
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Days to maturity: 100-120 days from planting to physiological maturity
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Planting depth: 1-1.5 inches

Soil

Type: Well-draining loamy soil with good organic matter content
pH: 6.0-7.0
Amendments:
Compost or aged manure for organic matter Inoculant containing Bradyrhizobium japonicum (nitrogen-fixing bacteria) Balanced fertilizer if soil is deficient in phosphorus and potassium

Growing Zones

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Thrives in zones 4-8; prefers regions with 120-140 frost-free days

4a 4b 5a 5b 6a 6b 7a 7b 8a 8b

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Growth Stages

1

Seedling

2-3 weeks

Cotyledons emerge, followed by first true leaves with characteristic oval shape. Plant is low to ground with minimal branching.

Keep soil consistently moist. Thin seedlings if necessary to proper spacing. Monitor for damping-off disease in overly wet conditions.

2

Vegetative

3-4 weeks

Plant establishes root system and develops compound trifoliate leaves. Stem becomes thicker and additional branch nodes form. Height reaches 12-18 inches.

Maintain adequate moisture and provide steady nitrogen fixation support. Control weeds to reduce competition. Monitor for early pest infestations.

3

Flowering

3-4 weeks

Small clusters of white, pink, or purple flowers appear at leaf axils along the stem. Plant reaches maximum height of 20-30 inches.

Critical period for water consistency; maintain regular irrigation. Avoid nitrogen fertilization which can inhibit nodulation. Continue pest monitoring.

4

Pod Development

3-4 weeks

Flowers give way to elongated green pods containing 2-3 beans. Pods gradually fill and mature. Lower leaves begin to yellow.

Maintain consistent watering during this critical stage. Support plant if lodging begins. Watch for pod-feeding insects and diseases.

5

Maturity and Harvest

2-3 weeks

Pods turn brown and dry; leaves yellow and drop. Plant desiccates; beans inside rattle when shaken. Plant is ready for harvest.

Allow full maturation for grain harvest. For edamame, harvest while pods are still green and beans are tender. Monitor harvest timing to avoid over-drying.

Companion Planting

Plan your garden →

Plant with:

Avoid planting near:

Fennel Kochia Alfalfa Other legumes in rotation Allelopathic crops

Common Pests

  • Hand-pick in early morning, use row covers during young stages, apply neem oil or insecticidal soap if infestation is heavy

  • Monitor populations; use reflective mulches, encourage natural predators, spray insecticidal soap or neem oil if thresholds exceeded

  • Increase humidity and irrigation, spray with water to dislodge, apply sulfur dust or miticide in severe cases

  • Use row covers early season, hand-pick beetles, apply spinosad or pyrethrin if population is damaging

  • Plant resistant varieties, ensure well-draining soil, avoid overwatering, practice crop rotation

Uses

🍳

Edamame and Fresh Beans

Culinary

Young green pods can be harvested for edamame, steamed with salt as a nutritious appetizer or snack. Mature beans are used in cooking, tofu production, tempeh, and soy milk. [source]

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Protein-Rich Food

Culinary

Amsoy soybeans are exceptionally high in protein (36-40% by dry weight) and contain all essential amino acids, making them a complete plant-based protein source for human consumption and livestock feed. [source]

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Animal Feed and Meal

Household

Soybean meal is widely used as high-protein livestock feed for poultry, cattle, and other animals. The oil is extracted for cooking and industrial uses. [source]

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Isoflavone Content

Medicinal

Soybeans contain isoflavones such as genistein and daidzein, compounds studied for their potential health benefits in human nutrition and wellness. [source]

🎨

Soy Candles and Biofuel

Craft

Soybean oil is used to produce eco-friendly soy candles and biodiesel fuel, making it a renewable alternative to petroleum-based products. [source]

This is not medical advice. LizPlants is not a medical resource. Always consult a qualified healthcare professional before using plants medicinally.

Harvest Tips

For grain soybeans, allow pods to mature fully until brown and dry, then harvest by cutting at soil level or pulling. For edamame, harvest when pods are bright green and beans fill the pod but are still tender, typically 90-100 days after planting. Edamame should be boiled or steamed immediately after harvest for best flavor. Grain soybeans should dry further after harvest for storage.

Fun Facts

  • 🌱 Amsoy soybeans are a determinate variety, meaning they mature all pods around the same time, making mechanical harvesting more efficient than indeterminate types.
  • 🌱 Soybeans form a symbiotic relationship with Bradyrhizobium bacteria in root nodules, fixing atmospheric nitrogen and naturally improving soil fertility—eliminating or reducing the need for synthetic nitrogen fertilizers.
  • 🌱 Amsoy was developed by the USDA and University of Illinois breeding programs specifically for the Midwest climate, making it one of the most widely planted soybean varieties in North America.

Gardening Terms

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