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Ironweed

Botanical Name
Vernonia spp.
Min Zone
4
Max Zone
9
Height
4 to 8 feet
Width
2 to 4 feet
Flowers
July to September: purple-violet cyme
Light
Full sun
Soil
Moist to wet soil
Planting & Care
  • Self seeds and can spread rapidly
  • Deadhead to control self seeding
  • Plants can be trimmed back to ground level in late spring to control height
  • Tolerent of brief flooding
  • Plants grow taller in wet soils
Problems
None serious
Varieties
  • Vernonia lettermannii 'Iron Butterfly' - this species is native to gravely plains making it very tolerant of hot and dry conditions and still tolerant of periods of flooding, fine foliage resembling Amsonia hubrichtii, compact 30 to 36 inches tall and wide
  • V. angustifolia 'Plum Peachy' - narrow leaves, 4 feet tall and wide
  • V. noveborecensis - 4 to 8 feet tall
  • V. fasciculata - 2 to 4 feet tall
  • Vernonia 'Summer's Surrender' - bushy habit produces a large, broad mounded plant in time, good resistance to powdery mildew and rust, fine foliage
  • Vernonia 'Summer's Swan Song' - fine textured foliage, rounded mound up to 30" tall by 40" wide

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