Purple Flowering Groundcover - Campanula Portenschlagiana - a plant that grows in less-than-ideal conditions and has long-lasting foliage. Plant care info is on the post - via Northern Shade - Gardening Daily
Liriope muscari - We need 19 Easy to grow, and spreads. Good for lining sidewalks. I have these and the flowers are a pretty shade of purple. Bees and butterflies like them. In winter, they produce interesting large seeds. - Ali C.