The objective of this study will be to determine the feasibility of a soybean-sorghum double crop system in South Carolina. Additionally, management strategies will have to be developed that will not negatively impact either crop. Potential synergies might be discovered between the two crops pertaining to weed control, nutrient recycling, beneficial insect populations, and more. South Carolina soybean farmers could increase their land use efficiency which would benefit the environment and their balance sheet. I will attack this issue from two sides. A soybean first and a sorghum first rotation. A field at Clemson’s Edisto REC will be split in half. On one side, group 4 soybeans will be planted as soon as possible. Research conducted by multiple universities in the mid-south on early soybean planting suggests that planting in early April can achieve maximum yields. Following these recommendations planting will happen when soil temperatures reach 55°F with a warming trend forecasted for the next 10 days. It will then be managed normally and desiccated at physiological maturity to allow earlier harvest. Ideally the soybeans would be harvested by late July and an early maturity sorghum will then be planted. The early maturing sorghum will reach maturity around 100 days which will put it maturing in late October. On the other half of the field, an early maturing grain sorghum will be planted as soon as possible. Current recommendations are when the soil reaches 60°F and warm conditions are forecasted for the next 10 days. Assuming this happens around April 1st, the sorghum will reach maturity around July 15th. The sorghum will be harvested and soybeans will be planted as soon as possible. Pioneer 95Y70 proved to be the highest yielding variety in the corn-soybean double crop study so it will be planted after the sorghum.
When all is said and done, if it doesn’t make money the farmers are not going to do it. All input costs will be recorded and an economic analysis will be conducted to determine the profitability of the double crop system. This will then be compared to a traditional single crop system for potential benefits.