Grapevine powdery mildew (GPM), caused by Erysiphe necator, is one of the most economically important diseases of Vitis vinifera grapes. Sulfur is the most common contact fungicide applied for GPM control. This thesis evaluated the potential of surfactants and air induction nozzles to enhance disease control afforded by sulfur. The capacity of sulfur to cause phytotoxicity during high heat and relative humidity conditions was also examined. Surfactants, when combined with sulfur, often increased GPM disease control over sulfur alone. However, the impact of adding surfactants varied by year. Air induction nozzles did not provide increased efficacy compared to the industry standard cone nozzles. Sulfur phytotoxicity was not observed when sulfur was applied in northern Georgia vineyards in mid- to late summer, as conducive conditions were not achieved. Historical data revealed that weather conditions conducive to phytotoxicity are exceedingly rare in the areas where V. vinifera grapes are grown in Georgia.