Chrysanthemum is my favorite flower, not only because they bloom in the season I was born, mostly because I had seen many spray mums in U.S. and people there decorated their yards and gardens with a lot of colorful mums.
Probably in Japan people don't favor mums so much, but they pick them anyway, because they are supposed to display mums while Ohigan (*Higan (two periods of seven days with the middle day falling on the spring or autumn equinox); the word higan meaning "the other shore," or, in Buddhism, nirvana. ) and other religious events. Or, they may get the idea of nationalism and maybe remind of imperial family. Japanese don't treat mums casually, but foreigners do, after I found that fact I love mums very much in my own casual way.
Chrysanthemum and pears