Using a combination of https://unix.stackexchange.com/questions/9883/how-can-i-run-a-script-immediately-after-connecting-via-ssh and nik's answer you can do:
ssh host.example.com -t '. /etc/profile; . ~/.profile; /bin/bash'
This will execute your profile scripts on login, then open a bash shell. Your profile scripts are where the colors are defined.
Or, for maximum convenience, add the following to your ~/.ssh/config
file:
Host * LocalCommand . /etc/profile; . ~/.profile; /bin/bash