Angelonia augustifolia or Summer Snapdragon can be grown as a perennial in Zones 9 - 11. Similar to Snapdragons, Angelonia bears small flowers on erect stems in shades of white, rose, violet and blue. Flowers bloom over several weeks, even months, during the summer. The original varieties of Angelonia were not particularly hardy, but a recently introduced cultivar ('Angelmist') is more vigorous.