The wild card for soybean production costs and for making money growing beans is the seed. In 2011, genetic trait-loaded soybean seed are expected to make up nearly half the total cost of production. More technology means more cost to farmers, so in some varieties with specific stacked traits the cost of seed could exceed 50 percent of the total production costs.

For example, the base price of one company’s Roundup Ready 2 Yield seed is $44.88 a bag for the lowest cost seed. The highest cost RR2 seed is $51.92 per bag. How high the final cost of soybean seed goes depends on what’s added to the seed, both genetically and conventionally.

Roundup Ready seed, by comparison, ranges from $37.22 to $42.19 a bag. Conventional seed with no genetic traits included sell for $30.80 per bag. Conventional insecticide and fungicide seed treatment will likely inch upward

Taking care of these high cost seed is critical to making money growing soybeans in the Southeast. Last year average yields in South Carolina were only 25 bushels per acres. In North Carolina and Virginia yields were about 10 bushels per acre higher.

Clemson University Agronomist Pawel Wiatrak says choosing the optimum soybean planting date will allow growers to reduce seed per acre without sacrificing yield.

His three-year research on evaluation of seeding rates in soybeans (across maturity Groups IV-VII) showed that seeding rates of soybeans can be reduced from high rates of 137,500 seed per acre to 82,500 seed per acre without a significant yield loss if soybeans are planted under optimum planting conditions by June 5. 

The caveat, Wiatrak says, is planting date. Highest yields across all maturity groups planted in South Carolina, he notes, were observed for soybeans planted from early May to May 20. In his research, soybeans planted after May 20 began losing yield at a rapid pace.

“Based on estimated yield loss, for each day of delayed planting the yield decreased by about 0.4 bushels per acre for soybean planting between May 20 and June 5, 0.3 bushels per acre for planting between June 5 and June 16, and 0.6 bushels per acre for planting between June 16 and July 2,” says the Clemson researcher.

The yield loss each year will depend on variety, location, availability of moisture and nutrients, and other planting and weather factors.