|I have a round concrete container maybe 18|
I am sorry for this delayed reply to your gardening question. We are transitioning to a new Q&A system and your question was unfortunately lost in the transition. I have discovered it now and hope this reply is not too late to be of help.
There are few shrubs small enough for such a small container. Dwarf yaupon would be okay as would a dwarf azalea. Another option would be to plant it with a dwarf gardenia.
Thanks for the question. Please stop in again soon!