Sugarcane flowering is a blessing in subtropical and temperate areas. It is intricate process subjected to a complex interaction of physiological and environmental facets chiefly plant maturity, photoperiod and temperature. Though at Murree, later two (environmental) parameters vary to bit extent from optimum, even then flowering does occur among good number of lines. Almost 41% of the lines grown during this study period flowered to different degree at 400m altitude. Lines were categorized as early (early November to July, 20 lines), intermediate (March to July, 45 lines) and late flowering (May to July, 21lines). Late flowering lines have relatively defined flowering period of 6 to 8 weeks. For sugarcane to flower, minimum physiological maturity is observed to be achieved when plant is about 75 days old or has developed 3 to 4 naked internodes. Shortening day length from 12h 30min to 12h was achieved in second week of September at 120 second per day. Average minimum temperature of (12.2oC) prevailed during flower initiation which was much below optimum requirement of 22oC. Low temperature resulted in variation in flowering among genotypes and was also responsible for reduced fuzz viability. Present study was conducted to ascertain factors responsible for sugarcane flowering at particular site. It will also help to plan future hybridization program in sugarcane.