Effect of Planting Date On Sweet Sorghum in Oklahoma.

The interest in sweet sorghum as a biofuel feedstock has created the need to determine the widest possible planting window to enable harvest to be spread out in the fall. In order to test the effect of staggered plantings, three different planting dates were evaluated at the Stillwater, Lane, Goodwell, and Haskell research stations and two different planting dates occurred at Chickasha and Altus from 2006-2008.  The planting dates ranged from April 20 to July 2.  Results indicate that satisfactory yields can be obtained across the range of planting dates tested.  Wet biomass yields ranged from 25 to 45 tons/acre, depending on location and variety, but there were no consistent significant differences due to planting date. Some difficulty in establishing crops at each targeted planting date was encountered due to weather in some locations, but once established, yields were very good.  In general, results suggest that a harvest window of 4-4.5 months could be achieved in most of Oklahoma with staggered plantings beginning in late April, and harvest taking place from August-November.