Lettuce emergence rate, seedling growth, and head size has been shown to positively correlate with seed vigor. Seed treatment practices in lettuce that increase seedling shoot mass can significantly influence lettuce growth, development, and final yield. This study investigated effects of lettuce seed treatment with Seed Power® (a nutrient solution containing cobalt and other proprietary compounds; Stoller USA) on lettuce seed germination, crop growth, yield, and potential interaction of Seed Power® with commonly used conventional fungicides.