Factors which explain supply response behavior of South Carolina tomato growers were determined. Two well known supply response models were used for comparison: the Nerlovian structural model and the Just risk model. The Just risk model reflected the significance of the risk effect in both stable and unstable periods. An evaluation of forecasting power between the two models was indeterminate. Growers are apparently willing to invest in more information with increased market instability because growers were influenced by the Florida winter price of tomatoes in planting decisions during the period of instability.