I am sorry for this delayed reply to your gardening question. The spring rush has brought a deluge of questions and we are working hard to catch up!
There are many options. For starters consider dwarf types of lantana, burgundy leaved types of begonias, Calylophus 'Southern Belle', purslane, portulaca, or dwarf celosia.
The following two web sites offer many more ideas:
Thanks for the question. Best wishes for a wonderful gardening season. Please stop in again soon!
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