The work aimed to determine the optimum conditions for the production of chrysanthemum flowers all the year, and identify the endogenous hormones associated with flowering. Three factors, including plant age, photoperiod and cultivar, were studied on potted chrysanthemum under fiberglass house conditions. Plants were used 1.5 months after the pruning of mother plants (old plants) or after propagation via terminal cuttings (new plants). Plants were exposed to five photoperiods including 4, 6, 8, 10 and 12 hours. The study was conducted on four commercial cultivars of different flower characteristics; yellow with small (YS) or big (YB) inflorescence, and red with small (RS) or big (RB) inflorescence. Old plants were better than new plants where their flowers production was 4 times higher. No flowers were obtained under 4 hours photoperiod. Flowers quantity increased with increasing photoperiod till 10 hours, the maximum flowering, then decreased under 12 hours. Flowering of chrysanthemum was cultivar dependent since cultivars of small flowers produced higher flowers quantity compared to those of big flowers, and the yellow cultivar gave the highest flowering. The optimum conditions allowed the production of 20-28 flowers per plant, depending on cultivar, with the highest quality expressed as flower stem length and flower diameter. The analysis of endogenous hormones showed that Indole Acetic Acid (IAA) and Gibberellic Acid (GA3) had an important role in flowering, on the contrary of Abscisic Acid (ABA). Both hormones correlated positively with flowering however, ABA correlated negatively with it. The concentration of IAA and GA3 during flowering was 3-4 times higher than ABA, and both were in high levels under the optimum conditions. The reported results could be useful on the applied level for the commercial production of chrysanthemum all the year, and the fundamental level for understanding the physiology of flowering process leading to plant improvement.