Planting the Seeds
Select the right type of seeds. There are thousands of different types of soybeans. If you want to eat your soybeans, make sure you have an edible, green variety. If you want to make soy milk or flour, find a yellow-seeded variety. If you are planning on drying the soybeans, get a black-seeded variety.
Pick the right soil.
Choosing the right soil for your soy plants has many advantages, including that there will be fewer weeds, less erosion, and the right balance of nutrients and pH in the soil. This will produce healthier plants with better yields.
- The best type of soil for soybeans is well-draining loam that isn't packed too tightly.
- If you're working with soil that has a high clay content, you can make it more suitable for growing soy by mixing it with peat moss, sand, or mulch.
Plant at the right time.
Soybean plants will generally produce the highest yields when the beans are planted in May, but the soil temperature is something you have to take into consideration as well.
- The ideal time to plan soybeans is two to three weeks after the last frost, when the soil warms to about 60 F (15.5 C) and the air to about 70 F (21 C).
Prepare the seedbed.
Soy plants need a good balance of nutrients in the soil to grow properly. If there are too many or too few nutrients, the plants won’t grow properly. Therefore, it’s important to add a fertilizer to the soil if the area hasn’t been enriched in recent years.
- For soil that hasn’t been enriched recently, add aged manure or compost to the soil to add more nutrients to the seedbed before planting.
Inoculate the seed.
One particular nutrient that soy plants require a lot of is nitrogen. The best way to ensure that they get what they need is to inoculate the beans with Bradyrhizobium japonicum, which is a nitrogen-fixing soil bacterium.
- To inoculate the beans, place the beans in a bucket and sprinkle them with the bacterium. Use a spade or small shovel to mix the beans and coat each one.
- Keep the seeds out of direct sunlight and plant them within 24 hours of inoculation.
- You can purchase Bradyrhizobium japonicum through catalogues, online, or in some gardening and farm supply stores.
Plant the seeds.
Sow the soybeans 1.5 inches (3.8 cm) deep into the soil, and space the beans about 3 inches (7.6 cm) apart. Plant the beans in rows that are about 30 inches (76 cm) apart.
- Water the beans once they’ve been planted, but only until the soil is moist. Do not overwater newly planted beans, otherwise they may crack.
Harvest
Pick pods that are in the middle of the plant as soon as they start to fatten up. By mid-September, you can pull up the whole plant and pick the remaining pods at your leisure. Edamame is the word used to describe the whole pods, which have been steamed or boiled, and optionally salted. The beans popped out of them for a delicious treat! The green vegetable soybeans freeze well after blanching.
