I don't know if bees can see colours, they certainly know light and dark
colours as they genarally attack black shoes, dark hair etc.. while
ignoring ones body if you are wearing white.
As to flower colours, I read somewhere that at the centre of each
flower thre is a hot spot which refects ultra violet light which the
bees can see.   I aslo beleive that bees use UV for navigation.
 
Philip Earle
QUB, N. Ireland.