Butterfly Bush

Butterfly Bush (Buddleia davidii)

Summer Lilac

Full sun, medium to moderately dry moisture, well-drained soil — tolerates poor, rocky, or compacted sites; neutral to slightly alkaline pH.

6–10 feet tall and wide in a single season in Middle Tennessee; blooms mid-summer through frost with fragrant panicles in purple, white, pink, or red; dies back to the crown in Zone 6b winters and re-grows from the base each spring; spreads aggressively by self-seeding.

Cut stems to within 12 inches of the ground in late winter before new growth emerges; this hard pruning produces the largest flower panicles on the current season's growth.

Native region: Not native to Tennessee; ornamental introduction from central China.

In Middle Tennessee's Zone 6b/7a transition zone, Buddleia davidii behaves as a die-back perennial rather than a woody shrub — stems killed to the ground by hard freezes, which actually controls size and promotes vigorous re-bloom. The plant performs well in the rocky, alkaline soils around older home foundations in Columbia and Maury County. Deadhead spent panicles before seeds mature to prevent aggressive naturalization; the species is listed as invasive in several southeastern states due to its prolific self-seeding in disturbed areas. Sterile or low-fertility cultivars (e.g., 'Miss Ruby', 'Pugster' series) are preferable. Attracts butterflies and hummingbirds, though it provides no larval host value for native insects.