If you colonize a system outside your colored influence area you create an outpost which carries this penalty, because its outside your influence. After 30 turns without being blockaded, your outpost becomes a colony therefor generates its own influence area thus removing the penalty and starting to get the expansion disaproval as Garm stated out. If another Planats influence area covers your outpost it wont get this penalty and instantly getting the expansion disaproval AFAIK!

If you colonize a system outside of your colored influence area you create an outpost which carries this penalty. After 30 turns without being blockaded, your outpost becomes a colony and therefore generates its own influence area thus removing the penalty and starts to get the expansion disapproval as Garm stated in the question comments.

As far as I know, if another Planets influence area covers your outpost it wont get this penalty and will instead instantly get the expansion disapproval.