Reddish-purple; can compare Phlox 'Delilah' with P. 'Düsterlohe" (Nicky) - purple, but perhaps a bit of bluer than 'Delilah' and P. 'Wendy House', purple but perhaps a bit redder than 'Delilah'. Suspect there's several relevant considerations here (e.g. perceptual colour differences between individuals (viz. human tetrachromacy)).