From the Ground Up: True blues in the garden are a rare find

I  never realized just how difficult it is to find true blue blooms until I wanted to plant a red, white and blue Marine garden.

I tried locally and online, but many times the blue turned out to be a lavender or shade of purple - and although beautiful, disappointing for a specific design. Well, what's up with blue in the garden?

In fact, less than 10 percent of the 280,000 species of flowering plants produce blue flowers.

David Lee, who wrote the book 'Nature's Palette: The Science of Plant Color,” explains: 'There is no true blue pigment in plants, so plants don't have a direct way of making a blue color. Blue is even more rare in foliage than it is in flowers.”

He added, 'Only a handful of understory tropical plants have truly blue foliage.”

Key ingredients for making blue flowers are the red anthocyanin pigments.

'Plants tweak, or modify, the red anthocyanin pigments to make blue flowers,” Lee said. 'They do this through a variety of modifications involving pH shifts and mixing of pigments, molecules and ions.”

These alterations, combined with reflected light through the pigments, create blue color.

While we are most familiar with flowers in hues of yellow, orange, red, and purple, the relatively few that are blue don't seem to deter pollinators. 'Insects and birds can widely detect blue as a wavelength,” Lee said. What they are looking for is a reward - like food - and blue flowers are just as capable of producing that as flowers of other colors.

Because of the high interest commercially, chemists have attempted to produce blue flowers in a number of our most popular garden and cut flowers, such as snapdragons, carnations and roses. Most frequently, the blue color is simply sprayed onto white blooms for corsages and arrangements.

However, chemists also have attempted to manipulate delphinidin, the pigment that makes delphinium and violas blue, to produce a true blue rose and carnation.

When a plant does bloom blue, it is spectacular. Blue plants add cool color to the garden and contrast well with yellows, oranges and reds.

Delphiniums are well-known for their various shades of blue and dramatic tall plumes. Blue hydrangeas also are garden showpieces for their large, puffball blooms.

Some perennials that are not as well known, but equally true blue, are the Blue Hyacinth, Plumbago, Blue Lobelia, Blue Scabiosa, Blue Larkspur and Blue Veronica.

All of these plants are relatively easy to maintain and loved by pollinators, so plan to add one or two to your garden this fall, and you'll enjoy their color next year.

' Becki Lynch is a Linn County Master Gardener. For gardening questions, contact the Linn County Master Gardener hotline at (319) 447-0647.