Giant ironweed
Vernonia gigantea
Asteraceae


Landscape Uses:

Wildflower gardens.

Ecological Restoration Notes:

Availability:
Commonly available at native plant nurseries in central Florida. Available at native plant nurseries in northeast Florida.
Description:
Perennial wildflower 3-4 feet tall with serrated, elliptic leaves 8 inches long. Showy purple flowers in clusters.
Height:
Typically 3-4 feet in height, much taller than broad.
Growth Rate:
Range:
Midwestern and south-central United States south to Sarasota to Martin counties.
Habitats:
Low, wet sites. Floodplains.
Soils:
Moist to wet, moderately well-drained to periodically inundated sandy, limestone, or organic soils, with or without humusy top layer.
Nutritional Requirements:
Moderate; can grow in nutrient poor soils, but needs some organic content to thrive.
Salt Water Tolerance:
Low; does not tolerate long-term flooding by salt or brackish water.
Salt Wind Tolerance:
Low; salt wind may burn the leaves.
Drought Tolerance:
Low; requires moist to wet soils and is intolerant of long periods of drought.
Light Requirements:
Full sun to light shade.
Flower Color:
Purple.
Flower Characteristics:
Showy.
Flowering Season:
May-December.
Fruit:
Wildlife and Ecology:
Attracts native bees and other beneficial insects. Valuable source of nectar for birds.
Horticultural Notes:
Comments:
We have been adding data for this species for central and northern Florida and welcome any feedback or review. If you would like to contribute information or images, please contact George Gann via the IRC staff page. See also the Florida Wildflower Foundation's Flower Friday page.


John Bradford
Shirley Denton