Part 3. Blue Flowers
By Mary Free, Extension Master Gardener
We wrap up our celebration of patriotic color flowers photographed on Independence Days of years past with those that are shades and tints of blue. Some of the pictured flowers may tend more toward a lavender hue, because in nature blue flowers constitute “less than 10 percent of the 280,000 species of flowering plants” according to David Lee, an emeritus professor at Florida International University.
Compact habit, prolific flowers, and dissected, gray-green foliage are enough to recommend Scabiosa ‘Butterfly Blue’ (pincushion flower) as an edging plant, for border fronts or rock gardens. It attracts bees and small butterflies, like the pictured skipper, and its long blooming period—from mid-spring until frost and even on mild winter days—makes it even more desirable. Photo © 2019 Mary Free.
Native Ruellia caroliniensis (Carolina wild-petunia), which can be found blooming in the demonstration Quarry Shade Garden, reseeds readily, so monitor its seed capsules because when mature they dehisce, burst open, spreading seeds where you may not want them. Photo © 2019 Mary Free.
In the Sunny Garden, Adenophora liliifolia (ladybells) blooms amidst the white shasta daises. Photo © 2019 Mary Free.
The flowers of Echinops (globe thistle), whether peaking or fading, are a decorative addition to the Sunny Garden. Despite their common name, these natives of Europe, Asia, and the mountains of Africa are not thistles. Photo © 2019 Mary Free.
If you want to attract robbers and hummers to your garden, then plant Salvia guaranitica (anise-scented or hummingbird sage). Don’t worry though, the only thing the robbers, like this Sunny Garden Apis mellifera (European honey bee), will steal is nectar (see Flowers That Attract Pollinators And Robbers To A Garden). Photo © 2019 Mary Free.
For Hydrangea macrophylla ‘Nikko Blue’ (bigleaf hydrangea), as for all cultivars except for those with white flowers, the more acidic the soil, the bluer the flowers. Photo © 2019 Mary Free.
Anthidium manicatum (European wool carder bee) sips the nectar of central Asian native Perovskia ‘Filigran’ (Russian sage). The bee’s common name describes its habit of scraping (carding) the hair from plants for its nest. The Latin name of this pollinator-attracting and sun-loving perennial describes its lacy (filigreed), silvery, and aromatic foliage. Photo © 2019 Mary Free.
Salvia x sylvestris ‘Blue Hill’ (wood sage) has a reputation for truer blue flowers, which attract a variety of bees, like this Bombus impatiens (common eastern bumble bee), and butterflies. Removing the spent flower spikes extends the bloom period through summer into fall. Photo © 2019 Mary Free.
Bees flock to the flowers of Agastache foeniculum (anise hyssop), a native of the upper Midwest. The white flowers of Southern native Hydrangea quercifolia (oakleaf hydrangea) are abloom in the background at the Glencarlyn Library Community Garden. Photo © 2019 Mary Free.