The Best Soil Temperature to Plant Soybeans

Germinating Temperature

• Warmer soil is key to quick soybean establishment, with optimum temperatures for germination and emergence ranging between 77 and 85 Fahrenheit. Soil that is too cold and wet may slow germination, making soybeans prone to damage from insects and soil pathogens. Soybeans germinate at a slower pace in low temperatures. At 46 F, for example, seeds take 40 days to emerge. Wait until soil is at least 65 F, at which point germination takes eight to 10 days.

Growing Soybeans

• Once soybeans are established, they grow well in soil at 60 to 65 degrees with a pH range of 6 to 6.5. Well-draining soil is best. Warm soil helps soybeans process atmospheric nitrogen, like other nitrogen-fixing legumes. They are assisted by the presence of bacteria in the soil that help them obtain the nitrogen. Soybeans also like direct sun and moderate, even moisture.

Planting Time

• Some growers plant soybeans early, while soil is still cool, to bring in a quicker or more economic harvest. But soybean farmers have to be aware of soil temperature and avoid sowing in cold, wet soil. Planting time varies by region and often occurs from May to mid-June. Early plantings as soon as late April sometimes produce as bountiful a harvest as a later-planted crop, providing economic benefits to farmers even when germination time is stretched.

Harvesting Soybeans

• The key to harvesting edemame is timing and diligence. The beans are their tastiest for just a few days and often ripen all at once, so staggered planting is better for continuous harvest. Pick when pods are deep green without any sign of yellowing. Since most are ripe at the same time, the entire plant may be cut down for pod removal.

  To cook the beans, boil or steam for five minutes and pop them out of their soft shells. The tasty pods are used as appetizers and added to all types of dishes. They provide Vitamin A, C and E as well as protein, calcium and phosphorus.