This experiment was performed to evaluate the effect of different nitrogen forms (ammonium to nitrate ratio) on the growth and flowering characteristics of two gerbera cultivars (‘Stanza’ and ‘Double Dutch’). The aim was to recommend the appropriate amount of NH₄⁺:NO₃^¯ ratio in the nutrient solution to optimize quantity and quality characteristics in gerbera. This experiment was conducted in a completely randomized design with factorial arrangement with two factors including NH₄⁺:NO₃^¯ ratios and cultivar type with three replications. The NH₄⁺:NO₃^¯ ratios (0:100, 20:80, 40:60, and 60:40) were supplied as the first factor and second factor was gerbera cultivars (‘Stanza’ and ‘Double Dutch’). The results indicated that increasing ammonium concentration in the nutrient solution to more than 40% of total N, significantly reduced growth indices and gerbera flower numbers compared to NH₄⁺:NO₃^¯ ratio of 20 to 80. Results showed that the highest flower number (314 flowers m^-2 year^-1), stalk dry weight (5.2 g), flower stalk diameter (0.92 cm), flower stalk weight (2.31 kg) and vase life (14 days) were obtained in 20:80 of NH₄⁺:NO₃^¯ ratio. Therefore, nutrient solution with NH₄⁺:NO₃^¯ ratio of 20:80 is an appropriate solution recommended for commercial production of gerbera cut flowers in order to achieve the optimum quantity and quality of cut gerbera.