My favorite Fall perennial is the chrysanthemum & I try to get as many different colors growing as I can. I have noticed though that the pretty white mums soon get a purple tinge to the white color every time I plant that color! What causes this to happen? Also, do I need to remove & plant fresh every few years? They seem to get rangy & sparse even though I prune them back during the summer (how late can I do this so I don't prevent any of the Fall blooms to develop? I prune to try & make them bushier & more flowers). I do plant the nice fresh prunings & often do get some of the cuttings to root, though the local snails sure do like the taste of new,fresh growth (they leave the old plants alone!)! The mums seem to bloom early, I clip the old blooms off & then they bloom as usual in the late Fall here.