Another group of seedlings prepared for Expt. 2 were used. On January 22, plants without visible buds were selected and three levels of irradiance, 45% shade (45% SH) from 08:00 to 20:00 h,30% shade (30% SH) from 08:00 to 20:00 h, and natural day (ND)were given between the intervals of 0–20 d, 21–40 d, and 0–40 d. Only the number of flowers was collected at flowering from 15 plants, which were completely randomized after each treatment period. Data were subjected to ANOVA with a factorial design with 2 growth stages and 3 irradiance levels.