In order to study flowering of Chrysanthemum coronarium, several investigations on the daylength, shading, irrigation and plant growth regulator treatment were carried out. As daylength was treated for 12, 14 and 16hrs, flowering was accelerated and plant height was increased. Leaf number, length and width were decreased by the increased daylength. Sensitivity to daylength and flower development were accompanied by the plant growth, especially the effect of long day treatment was appeared remarkably when the number of leaves was more than 8 leaves. The minimum days of long day treatment for flowering was more than 10 days. Flowering was delayed by 65% shading treatment, over irrigation.