It is a herbaceous perennial plant growing to 80 cm tall. The leaves are glaucous greyish green to blue-green, slender, up to 15 cm long. The flowers are produced singly or up to five together in a cyme; they are 3–5 cm diameter, and sweetly scented; the original natural flower colour is bright pinkish-purple, but cultivars of other colours, including red, white, yellow and green, have been developed Species 1. Killer. 2. Malaga. 3. Delphi. 4. Madame Colette. 5. Varna. 6. Solar 7. Lady Green 8. Pink Dona 9. Tundra 10. White Tundra