Plant name: New York ironweed
Botanical name: Vernonia noveboracensis
Virtues: Blooms in late summer and autumn; a tall, narrow plant for the back of the border or tight spaces; easy to grow; purple flowers attract butterflies and seed heads attract birds.
Flowers: Fluffy purple flowers appear in 3- to 4- inch clusters on 4- to 6-foot-tall stems in late summer.
Habit: Upright herbaceous perennial to 4 or 6 feet tall and 3 or 4 feet wide.
Season: late summer
Origin: Eastern United States
Cultivation: Prefers rich, moist soil but will tolerate any average soil with moderate to wet moisture. Full sun. Rust-colored seed heads appear after the flowers and attract birds. Plant will naturalize by self-sowing, so remove these if that is unwanted. USDA Zones 5 to 9.