Gentiana
If you were to select a genus of plants to typify blue flowers, the Gentiana is arguably the best. Intense shades of blue, with normally large, bell-shaped or starry flowers, which open in sun. Many grow on alpine meadows, rocky areas, in sun, but not intense heat. There are around 400 species and other colours are found, yellow, (G. lutea), along with pinks and white. A contrast to the sun-loving forms is the willow gentian, G. asclepiadea, which is happy in part shade and good soil, but it still rewards with the typical blue flowers at the ends of arching leafy shoots.