I love these. Plant them every year. Shade-Loving Annuals: Viola. 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 dizzying range of shades including many wonderful bicolors such as the 'Sorbet Coconut Swirl' shown here.