Bearded iris can bloom in almost any color. It is expected of them. There is not much they can do to surprise us.

Dahlias exhibit a remarkable range of both color and floral form. Only a few colors are beyond their range.

Roses, gladiolus, freesias, tulips, hyacinths, petunias, pansies, primroses and several of the most prolific bloomers are expected to provide many choices of color.

Other flowers are not so diverse. Forsythia blooms only in bright yellow, or perhaps a lighter hue of yellow. Mock orange blooms only in white, either single or double. Until recently, before purple was invented, the common species of lily-of-the-Nile were either blue or white. We tend to appreciate such flowers for their simplicity, and do not expect anything more from them.

Decades ago, hydrangeas were either white or pink or blue. I say ‘either’ because what seems to be three choices is actually only…