Yes perennials, and specifically I would recommend the plumbago. It has a really beautiful violet bloom and requires little water and sunlight to survive. I have planted them and they look great with little maintenance and grow between 6 to 12 inches tall.
Check out www.burpee.com They have a garden wizard where you select full sun/partial/full shade, care level, flower type & I think height level too. The sight has high-quality plants & a wonderful reputation for quality.
I love hydrangeas for the shade. Only certain types grow well here, but I'm placing great hopes on the new one coming out, Blushing Bride...sister to Endless Summer. I love reblooming perennials of any sort, but these are particularly lovely!