Iresine herbstii: A perennial bedding plant that is grown mainly for its spectacualr foliage which resembles a rare cooked steak. The leaves are 10 cms long, round to oval and purple in colour with brilliant red to pink veins throughout. The flowers are insignificant. There are green/yellow varieties as well - both being frost tender.
Make your shade garden easier to maintain. As an added bonus, many varieties provide an attractive carpet of color (such as this golden creeping Jenny, which practically glows underneath a planting of blue hostas, purple coleus, and black mondo grass).
Like lobelia, violas are cool-season plants that can take full sun in early spring and fall, but they'll bloom a bit later into the summer if you grow them in the shade, especially in the South. Violas bear flowers in a dizz