Phlox paniculata is a species of flowering plant in the phlox family (Polemoniaceae). It is native to parts of the eastern and central United States. It is extensively cultivated in temperate regions as an ornamental plant and has become established in the wild in scattered locales in other regions. Common names include fall phlox, garden phlox, perennial phlox, summer phlox, and panicled phlox.
Phlox paniculata is an erect herbaceous perennial growing to 120 cm (47 in) tall by 100 cm (39 in) wide, with opposite, simple leaves on slender green stems. The flowers are 1.5–2.5 cm (0.6–1.0 in) in diameter, often strongly fragrant and borne in summer through fall (autumn). The flowers are grouped in panicles (with many branching stems), hence the specific epithet paniculata. Typical flower colors in wild populations are pink or purple (rarely white).
Fall phlox is native to parts of the central and eastern United States. It occurs as an introduced species in other parts of the United States, Canada, Europe, and Asia. In the Chicago Region it is questionably native, or native populations may have all been destroyed: "populations in our area appear to be escapes from gardens to nearby woods and waste ground, which no doubt accounts for all collections since 1945".
In its natural range, it grows along streambanks and in moist wooded areas.