Glycine max – Soybeans

Prized for their nutrient-rich properties and their ability to enrich the soil, Soybeans (Glycine max) are a member of the pea (legume) family of vegetables. They are economically the most important bean in the world.

What are Soybeans?

• Soybeans are one of the predominant world crops and are grown for oil and protein.
• They are native to northeastern China, where they have been cultivated for thousands of years.
• Soybeans are upright, bushy annual legumes with dark green leaves and small, white to purple-pink flowers blooming from mid-summer to fall.
• They are followed by clusters of green, furry pods containing 2-4 plump, pale green beans.
• As opposed to Edamame beans, which are immature soybeans harvested when young and tender, Soybeans are left to mature and harden.
• Fully matured soybeans are light brown and are rather tasteless.
• Soybeans can be consumed in many ways (tofu, soymilk, sprouts, miso, soy sauce).
• Because they are rich in quality protein and digestible energy, they are also turned into animal feed. Soybean oil has many uses, such as cooking oil, biodiesel and bioheat, and non-toxic industrial supplies.
• Like most other beans, Soybeans fix nitrogen and add nutrients that improve the soil, benefitting the plants that are growing beside them. Beans are great for heavy nitrogen users.

Health Benefits of Soybeans

• Soybeans are a healthy source of high-quality protein, are low in saturated fats, and are high in iron and fiber when prepared properly.
• Proteins: one cup of Soybeans contains 31% of your daily protein needs. Proteins benefit a healthy immune system and help maintain healthy bones, hairs, organs, and muscles.
• Soy Proteins, unlike animal proteins, help reduce bad cholesterol. They also aid in creating muscle mass and strength.
• Soybean oil is one of the few non-fish sources of omega-3 polyunsaturated fatty acids and may reduce blood pressure and the risk of heart disease.
• Isoflavones: may help prevent dementia and cognitive decline, reduce the risk of various cancers, such as breast, lung, and prostate, improve skin health and reduce wrinkles.
• Iron: one cup of Soybeans contains 49% of your daily recommended intake. Iron can help prevent anemia.
• Potassium: one cup of Soybeans contains 25% of your daily needs. Potassium plays a role in kidney health, bone and muscle maintenance, blood pressure, and cardiovascular health.
• Fiber: may help lower harmful cholesterol levels and improve your heart health. Fiber also helps regulate the digestive tract and keep your digestive system healthy.
• Low glycemic index: making Soybeans suitable for people with diabetes.
• Nutrition Facts (per 100 grams): 170 calories, 8 grams carbs, 18 grams protein, 9 grams fat, 6 grams fiber.

Cooking with Soybeans

• Raw Soybeans are toxic to humans as they contain trypsin inhibitors that affect digestion and can lead to organ damage.
• They must be cooked with wet heat or fermented to be fit for consumption.
• To cook dry Soybeans, rinse them, soak them for 6-8 hours or overnight, boil them for 5-6 hours, and drain and remove the hulls.
• Soybeans are used in Chinese and Japanese cuisines in dishes like Edamame and are commonly blanched, boiled, or steamed.
• Soybeans pair well with flavorings like ginger, garlic, sesame oil, rice wine vinegar, soy sauce, and red pepper flakes.

Growing Soybeans

• Soybeans grow up to 2-6 ft. tall (60-180 cm) and 2-3 ft. wide (60-90 cm).
• They perform best in fertile, acidic (pH of 6.0), moist, well-drained soils in full sun (at least 6 hours of direct sunlight per day) in a sheltered location.
• If the soil lacks nutrients, add well-rotted organic matter or compost 2-4 weeks before planting.
• While fairly drought-tolerant, Soybean plants will produce more if they are kept moist throughout the growing season.
• Bean plants do require consistent and even moisture once they have formed flowers.
• Soybeans take 100 days or more to harvest after planting.
• Soybeans are a warm-season crop that grows best between 60-70°F (15-21°C).
• Sow seeds outdoors in the spring when the soil has warmed to at least 55°F (13°C) and air temperatures have reached at least 60°F (16°C).
• Planting in cold, wet soil can cause soybean seeds to rot.
• Sow ¼ to ½ of an inch deep (0.5-1 cm) and 2-4 inches apart (5-10 cm) in rows 2 feet apart (60 cm). Water thoroughly. Germination takes 1 to 2 weeks.
• Thin seedlings to 6 inches apart (15 cm) when the plants are 4 inches tall (10 cm).
• Weed around plants regularly and keep them well watered.
• Beans are soil builders. They rarely need any fertilizer during the growing season.
• Mulch to retain moisture, keep the soil cool, and control weeds.
• Rotate crops: Prevent problems by not planting beans in the same location more often than every 3 years.
• Soybeans are susceptible to a few pests. Keep an eye out for aphids, Mexican bean beetles, root-knot nematodes, slugs, snails, stink bugs, whiteflies, and wireworms.
• Soybeans are susceptible to diseases, including anthracnose, powdery mildew, soybean rust, root rot, stem rot, stem blight, and white mold.

Harvesting and Storing

• Harvest when the pods appear full and green if growing as a vegetable (Edamame).
• Otherwise, harvest pods after they turn yellow.
• Ripe soybeans are ready for harvesting when the leaves start to fall, often leaving just brown stems with plenty of hanging pods.
• When harvested fresh, Edamame should be used immediately for the best flavor and will keep for 1 to 2 days when stored in the refrigerator.
• Once cooked, Edamame beans can be stored in the refrigerator for up to 10 days. Frozen Edamame will keep for 6 to 8 months.
• Shell dried mature Soybeans and place them in an air-tight container. They can be stored for 1-2 years in a cool, dry place.

Best Companion Plants

• Celery and beans seem to help each other.
• Collard intercropped with beans can increase the yield of both crops.
• Corn benefits from the nitrogen added to the soil by the beans. Soybeans planted near corn protect it against chinch bugs and Japanese beetles.
• Cucumbers do well when planted with beans, as they are mutually beneficial.
• Kale profits from being grown with nitrogen-fixing legumes like beans.
• Marigolds attract beneficial insects that deter pests like Mexican bean beetles and whiteflies.
• Potatoes protect beans from the Mexican bean beetle. In return, beans planted with potatoes protect them against the Colorado potato beetle.
• Spinach benefits from the natural shade provided by the beans.
• Summer squash benefits from the nitrogen added to the soil by the beans. The large leaves of the squash vines create a protective mulch that helps retain moisture while suppressing weeds.
• Strawberries and beans are mutually helpful, both growing more quickly than if planted alone.
• Swiss Chard and beans are mutually beneficial. The nitrogen-fixing legumes enrich the soil, while Swiss chard helps increase the chlorophyll production of the legumes.

Worst Companion Plants

• Do not plant beans near garlic, onions, chives, leeks, scallions, shallots, peppers, wormwood, fennel, or gladioli.
• Alliums such as garlic, onions, chives, leeks, scallions, and shallots will stunt the growth of the beans.
• Most plants dislike fennel, and it has an inhibiting effect on them.