Gardening Articles: Flowers :: Perennials
Wild Blue Phlox (page 2 of 3)
by Dorothy J. Pellett
Choice Varieties of Wild Blue Phlox
Alan L. Summers, president of Carroll Gardens in Westminster, Maryland, recommends 'London Grove Blue' as the most desirable cultivated variety. It has large periwinkle blue blooms and a stronger fragrance than the wild blue phlox does. Bright white flowers are found on 'Fuller's White'. 'Dirigo Ice' and 'White Perfume' are silvery blue.
Other varieties with deeper shades of purple-blue include 'Chattahoochee', 'Eco Texas Purple', and 'Louisiana Purple'.
The individual flowers of the purple-blue kinds are lovely, but usually smaller than those of other varieties. Ainie Busse, owner of Busse Gardens in Cokato, Minnesota, recommends 'Chattahoochee' as a vigorous grower there (zone 4). All bear flower clusters atop 10- to 18-inch stems; bloom lasts for three to four weeks.
For gardeners interested in the history of their plants, P. divaricata is the subject of a surprising tale. Some of these plants are believed to have survived the hot, dry periods between ice ages. One colony, with unnotched flower petals, spread westward from areas in what is now Missouri to areas of present-day Nebraska and Kansas. These plants are now designated P. divaricata laphamii. Another colony with notched petals survived in the Appalachian highlands and, with the return of favorable growing conditions, spread throughout the eastern part of the United States. The two colonies have mingled in overlapping ranges, with variations in the flowers' shape and color.
From Pennsylvania southward, native stands of P. divaricata include pink-flowered forms mingled with the blue. Charles Oliver of Scottdale, Pennsylvania, has bred large-flowered and pink types, not yet introduced to the nursery trade but expected to be available in a few years. Oliver has also developed hybrids of P. divaricata and P. amoena, a species native to southeastern states. One such cross, 'Charles' Passion', has glowing purple flowers. It, too, is still rare in cultivation. The plant I have grown for two years has been hardy where I live in zone 4b, despite its southern heritage. (Because soil acidity, moisture, and fertility all influence P. divaricata hybrids' flower color, before new varieties are named, they are grown long enough to ensure that their features are uniform under all conditions.)