Lindley butterfly bush arrived in American gardens in the 1800s and has remained something of a quiet discovery ever since — overshadowed by showier Buddleja davidii cultivars but offering something none of them can match: a genuinely weeping habit, with long, pendulous panicles of lavender flowers that nod and sway on arching branches. In its homeland of Southern China, it colonizes roadsides and railroad embankments with a casual wildness, and that same easy vigor translates well to the garden, where it fills space generously and blooms reliably on new wood each season.

Grow it in full sun with moist, well-drained soil and it will reward the effort with fragrant late-season color that bees find irresistible. Prune hard in late winter before new growth emerges, since flowers form on new wood — this keeps the weeping form tidy and prevents the plant from sprawling beyond its allotted 5 to 8 feet. Mulch generously and deadhead spent panicles to encourage a second flush. It spreads by suckers, so watch the margins of the planting and remove unwanted growth before it becomes a habit.