From this site :
What some call wacky, others call a way of life. Take the Texas Homecoming Mum-- a symbol of Texas football and an annual rite of passage for high school ladies.
Bought by the girl's date, the mum is a mix of flowers, yards of ribbon, trinkets, charms, stuffed animals and sometimes even cow bells ... all pinned to the shirt. The mum's size has a direct relation to how much the guy likes the girl. Some mums require a lanyard around the neck to support the weight. That's a whole lotta love.