Phlox carolina, the thickleaf phlox, is a species of flowering plant in the family Polemoniaceae. It is an herbaceous perennial growing to 1.2 m (4 ft) tall by 45 cm (18 in) wide, with leaves to 13 cm (5 in) long, and purple or pink flowers in summer.The specific epithet carolina refers to its native habitat in the eastern United States. It is the parent of numerous garden cultivars, of which 'Bill Baker' and 'Miss Lingard' have gained the Royal Horticultural Society's Award of Garden Merit.