Spanning the Southern and Central Appalachians, the Blue Ridge Parkway offers an exceptional glimpse of the Appalachian flora, which is world renown for its diversity. There are currently over 1,400 species of vascular plants known to occur in the park, though this number may well likely approach 2,000 species as the park begins an extensive inventory of all plants and animals. The flora of the Blue Ridge Parkway is so diverse for reasons such as, climatic variability, large north-south geographic range, diverse geologic substrate, and many different micro-habitats. Because of the wide range in elevation from high peak to low valley, the park visitor can enjoy a tremendous variety of wildflowers throughout the spring, summer, and fall months. While the summer wildflowers are blooming in the valleys, the spectacular spring wildflowers are just beginning to bloom on the high peaks. The following showy wildflowers are commonly found from May to August: Turk’s Cap Lily (Lilium superbum), Pink Lady's Slipper (Cypripedium acaule), Evening Primrose (Oenothera fruiticosa), Bee Balm (Monarda didyma), and Fire Pink (Silene virginica).
The Blue Ridge Parkway is unique in that it covers a wide range of habitats along the north-south axis of the Appalachian Mountains, such that the flora on a mountain summit at the northern end of the park may be quite different from the flora of a mountain summit at the southern end. Some of these habitats are exceptionally rare in the region and a few are even globally rare. An example includes rock outcrops at high elevations, which contain a fragile group of alpine species that were pushed southward during glacial times and eventually were left stranded on the southern mountains. The main threat to this fragile plant community is trampling by unaware park visitors. Another unique habitat is the Grassy Balds which were likely grazed by native animals such as bison and elk, but which now are maintained by park biologists.
The same environmental variability that leads to such spectacular bloom displays in the spring and summer also contributes to autumn leaf color. The first leaves to change are those of deciduous trees on the highest elevations, which change to vivid shades of orange, red, yellow, and purple. Throughout the month of October the leaf color changes gradually, beginning in the high mountains and concluding at the lower slopes and valleys.