Plant Catalog › Vernonia lettermannii 'Iron Butterfly' Vernonia lettermannii 'Iron Butterfly' $0.00 Common Name: Narrow-leaf Ironweed IronFull SunBlooms: Late summer into FallH: 30-36" W: 30-36"Color: Purple Shades Add To Cart Added! Common Name: Narrow-leaf Ironweed IronFull SunBlooms: Late summer into FallH: 30-36" W: 30-36"Color: Purple Shades