Ascorbic acid (Vitamin C) is a growth regulator that stimulates plant growth and development. First, a preliminary experiment was performed to find the optimal Vitamin C dosage for maize plants. A single genotype of maize, Golden, was grown in sand under pot conditions. Hoagland’s nutrient solution was applied for seven days. Four doses of Vitamin C (i.e., 0.5, 1, 1.5and 2 mM) were applied as foliar spray on maize seedlings for two weeks. Then, in the main experiment, two genotypes of maize (Zea mays L.) namely Golden and Agaiti 2000 were grown in soil in a wire house at the Botanical Garden, the University of Agriculture in Faisalabad (Pakistan). Based on the preliminary results, the optimal dose (2 mM) of ascorbic acid was applied exogenously as foliar spray on leaves of both genotypes every third day for five weeks at seedling stage (3 leaf stage). Findings were noted both qualitatively and quantitatively in terms of different physiological and growth parameters. In addition, COSTAT software was employed to perform statistical analysis of quantitative readings for all parameters using analysis of variance (ANOVA) technique. It was observed that treated plants showed improved health and growth compared to non-treated plants with higher contents of physiological variables including chlorophyll, carotenoids, soluble carbohydrates, and minerals etc. and increased leaves, roots and shoots sizes and biomass. Moreover, Agaiti 2000 genotype was observed to show better results than genotype golden.