The publishing company of Hana Yori Dango (花より男子 カラー版) released the coloured versions of the manga. It can be purchased online but I honestly don’t think the quality is that great. 
Author: Kamio Yoko
Language: Japanese (raws)
Volumes: 1 of 37
Download »70.35 MB
do u know if there’s an english colored edition?
Not to my knowledge.