Phlox is a genus of flowering plants, native primarily to North America, that has become a garden favorite globally due to its long blooming season and diverse forms. These plants include both tall, upright perennial varieties and low-growing, mat-forming types. Phlox is celebrated for offering one of the broadest and most vibrant color palettes available in garden ornamentals. The genus encompasses a spectrum of hues, making it a versatile choice for gardeners looking to introduce expansive color into their landscapes.
The Core Color Palette
The majority of Phlox cultivars available today are rooted in a foundational color palette derived from their wild ancestors. Pink is the most prevalent color, spanning a wide range from palest blush to vivid magenta and deep cerise. These pink tones are highly stable and reliably expressed across various species and growing conditions. Pure white flowers are also common and widely used in breeding programs, offering brilliant, snow-white petals or softer, creamy-white shades. Lavender and light purple hues form the third pillar of the core palette, providing cool-toned options. These foundational colors—pinks, whites, and lavenders—represent the most genetically dominant and readily available options for the average gardener.
Color Variation Across Phlox Types
The availability and intensity of colors are closely tied to the plant’s growth habit and species, which are divided into groundcover and upright varieties. Tall Garden Phlox (Phlox paniculata) is the primary source for deeper, saturated shades suitable for mid-to-late summer borders. This upright species yields rich purples, deep magentas, and near-reds. In contrast, Creeping Phlox (Phlox subulata) and Woodland Phlox (Phlox divaricata) form low, dense mats in the spring and feature a different range. P. subulata is known for electric pinks and whites, while P. divaricata offers some of the softest blue-lavender colors found in the genus. The distinct genetic makeup of these different species determines which colors can be expressed and successfully stabilized in a commercial cultivar.
Unique and Rare Color Hues
The most sought-after hues in Phlox deviate significantly from the common pinks and purples, particularly “true” reds and blues. Achieving a genuine, saturated red has been a challenge, as most cultivars labeled as red have strong undertones of scarlet, crimson, or magenta. A true blue Phlox remains elusive; most blue-toned varieties present as a soft violet or lilac-blue, often deepening in color under cooler conditions. Beyond solid colors, unique patterns represent another area of specialty breeding. Many modern cultivars feature a contrasting “eye,” where the center of the flower tube is a different color from the surrounding petal lobes, or are bi-colored and variegated.