Ironweed

Vernonia
A genus of perennials that are part of the larger Daisy family, that are valued for their late summer and autumn flowers. Tough as Iron, I object to them having weed in their name, being far too beautiful. Rarely used in landscaping, many species are very ornamental and have high value as landscape plants. The flowers attract hummingbirds and butterflies.
Propagation can be from softwood cuttings taken during late spring and division.
Seed should be collected during autumn and cold-moist stratify for 3 months in the refrigerator. Sow thickly as rates of germination are not that high.
The Ironweed tolerate Juglone from Walnut tree roots and are rarely eaten by deer or rabbit.

* photos taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

Vernonia angustifolia ( Narrowleaf Ironweed )
A robust, shrubby perennial, reaching a maximum size of 6 x 6 ( rarely over 4 x 4 ) feet, that is native to oak woods and pine barrens in the southeastern U.S. ( from central Mississippi to North Carolina; south to Louisiana to central Florida ). It is threatened in North Carolina.
The linear leaves, up to 5 x 0.3 inches, are deep green. The foliage and habit, resembles that of Amsonia hubrechtii.
The deep violet flowers, up to 1 inch across, are borne in large, airy flower heads, up to 8 inches across, all summer long. The stems are sturdier than most other species. The flowers attract hummingbirds.
Hardy zones 4 to 8 in full sun on acidic to neutral, sandy, well drained soil. It is very drought tolerant.

* photo taken on July 21 2019 @ London Town Gardens, Edgewater, MD

* photos taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

var mohrii
Narrower leaves, otherwise identical to species. It is found in the wild from central Mississippi to far southern Georgia; south to central Florida.

* photos taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photo taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

'Plum Peachy'
Sturdier and shorter in stature ( up to 4 feet ) with deep purple flowers.

Vernonia baldwinii ( Western Ironweed )
An aggressive spreading, rhizomatous perennial, reaching up to 5.7 x 4.2 ( rarely over 5 ) feet, that is native to prairies the western U.S. ( Colorado to western South Dakota to central Minnesota to far southwest Michigan; south to eastern New Mexico to northern Louisiana ). It is endangered in South Dakota, Minnesota, Wisconsin, Michigan, Indiana and Colorado.
The long, lance-shaped leaves, up to 7 x 3 inches in size, are mid-green.
The intense, violet-red flowers are borne on fussy, dense heads, up to 6 inches across, from late summer until autumn frosts.
Hardy zones 3 to 8 in full sun on just about any well drained soil.

* photos taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

* photo of unknown internet source


Vernonia crinata ( Arkansas Ironweed )
Also called Vernonia arkansana. A very large perennial, reaching up to 10 x 6 ( rarely over 6 ) feet in size, that is native to wet meadows from eastern Kansas to central Illinois; south to eastern Oklahoma to northern Arkansas ).
The narrow lance-shaped leaves are up to 8 x 1 inches in size. The attractive foliage is glossy mid-green.
The violet-purple, daisy-like flowers, up to 1 inch across, borne on loose clusters during mid to late summer.
Hardy zones 3 to 8 in full sun to partial shade on just about any moist soil.

Vernonia fasciculata ( Prairie Ironweed )
A vigorous but compact perennial, reaching up to 8 x 6 ( rarely over 3.5 ) feet in height, that is native to moist prairie and floodplain forests in central North America ( from north-central Montana to southeast Saskatchewan to southern Manitoba to Wisconsin to northern Ohio; south to Oklahoma to western Kentucky ). It is extinct in Saskatchewan & Colorado. It is endangered in Manitoba, Arkansas and Ohio. In the Windsor/Essex County, Ontario region; it was only noted as occurring on the Ohio shore where locally common during the 1800s. A single plant may have up to 11 stems.
It is among the most ornamental of the Ironweed.
The lance-shaped leaves are up to 8 x 1.6 inches in size. The attractive foliage is gray-green.
The violet-purple flowers are borne late summer into early autumn.
Hardy zones 3 to 8 in full sun to partial shade on wet soil though it can tolerate temporary drought.

* USDA-NRCS PLANTS Database

Vernonia gigantea ( Giant Ironweed )
Also called Vernonia altissima. A vigorous perennial, reaching a maximum size of 15 x 7 ( rarely more than 8 ) feet that is native to open woods, bottomlands and swamps in eastern North America ( from eastern Nebraska to northeast Iowa to southern Wisconsin to southern Michigan to Grand Bend, Ontario to central New York State; south to eastern Texas to central Florida ). It is endangered in Nebraska, New York State, Maryland, North Carolina and Texas. In the Windsor/Essex County, Ontario region; it was locally common at the Ojibway Prairie in Windsor and from the Canard River Valley to the town of Essex during the 1800s. Giant Ironweed is now critically endangered in Ontario, Canada. It was rare at Detroit at that time and has declined since. On the Ohio shore, it was abundant during presettlement era.
The narrowly-ovate to elliptical leaves are up to 12 x 2.5 inches in size. The foliage is deep green above, bright green beneath.
The vivid rose-purple flowers are borne on massive flattened panicles, up to 16 inches across, during late summer into early autumn.
The stems are usually purplish-green.
Hardy zones 4 to 9 ( 3 on protected sites ) in full sun to partial shade on any fertile, moist soil.

* photos taken on Aug 13 2017 @ Howard Comm. College, Columbia, MD

* photo taken by Clarence A. Rechenthin @ USDA-NRCS PLANTS Database

* USDA-NRCS PLANTS Database

'Jonesboro Giant'
A massive sturdy form sold by Plant Delights that originated in Jonesboro, Arkansas.
Hardy zones 5 to 9.

Vernonia glauca ( Upland Ironweed )
A perennial, reaching up to 6 x 5.3 ( rarely over 5 ) feet. It is mostly native to the Piedmont from central West Virginia to southeast Pennsylvania and New Jersey; south to northern Mississippi to southern Alabama to central South Carolina. It is also native to southeastern Massachusetts, central Kentucky and Tennessee. It is endangered in Mississippi, West Virginia, Maryland, Delaware, Pennsylvania and New Jersey. It is likely extinct in Kentucky and Tennessee.
The toothed, lance-shaped leaves are up to 8 x 3 inches in size. The attractive foliage is deep green above, bluish-white beneath.
The deep purple flowers are borne on upright flat-topped panicles during late summer into early autumn.
Hardy zones 6 to 8 ( should be tested in 5 ) in full sun to partial shade on just about any moderately moist, well drained soil.

* photos taken on Aug 13 2016 in Reisterstown, MD

* photos taken on Sep 16 2016 @ Patuxent Research Refuge, Laurel, MD

* photo taken on Aug 4 2021 @ U.S. National Arboretum, Washington, DC

* photo taken on Aug 30 2021 @ U.S. National Arboretum, Washington, DC

* photos taken on Aug 24 2024 @ Howard County Conservancy, Woodstock, MD

* photos taken on Sep 3 2024 in Columbia, MD

Vernonia lettermannii ( Letterman Ironweed )
A fast growing, dense, compact perennial, reaching up to 4.3 x 6 feet, that resembles Amsonia hubrechtii in habit and natural range. It is native to rocky soil and floodplains in Oklahoma and Arkansas. It is rare in cultivation and endangered in the wild, most of its native range is in the Ouchita River basin in Arkansas.
It has high potential as a landscape plant for the perennial border and masses in commercial shopping centers where it tolerates reflected heat off pavement.
The fine-textured, linear leaves, up to 3.5 x 0.15 inches, are mid green. The very attractive luxuriant foliage makes this plant very attractive even when not in bloom.
The purplish-pink flowers are borne on flower heads late summer to early autumn.
Very abundant blooming, a single plant may bear hundreds of flowers at a time.
The flowers attract butterflies and hummingbirds.
Hardy zones 4 to 9 in full sun on well drained soil. Tolerant of drought and extreme heat, it will also tolerate floodplain sites which occasionally flood. Too much water and fertilizer can make it less sturdy and flop over, it is not tolerant of heavy wet clay.

* photos taken on August 25 2011 @ Scott Arboretum, Swarthmore College, PA



* photos taken on June 30 2013 @ U.S. National Arboretum, DC

* photos taken on Sep 14 2013 in Columbia, MD

* photos taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

'Iron Butterfly'
Very vigorous and densely branches, with deep violet flowers, otherwise similar.

* photo taken on Sep 22 2013 in Harford Co, MD

* photos taken @ U.S. Botanical Garden, Wash., DC on Aug 25 2014

* photos taken on Nov 14 2015 in Harford Co., MD

* photo taken on Oct 2 2016 in Harford Co., MD

* photos taken on Aug 5 2017 @ Brookside Gardens, Wheaton, MD

* photos taken on Aug 24 2017 @ U.S. Botanic Garden, Wash. DC.

* photos taken on Sep 3 2017 @ U.S. National Arboretum, D.C.

* photos taken on Nov 9 2017 in Harford Co., MD

* photos taken on Nov 10 2020 @ Brookside Gardens, Wheaton, MD

* photo taken on Aug 30 2021 @ U.S. National Arboretum, Washington, DC

* photos taken on July 28 2024 in Columbia, MD

* photos taken on Aug 11 2024 in Columbia, MD

* photos taken on ASep 1 2024 in Columbia, MD

* photos taken on Oct 22 2024 @ Howard Comm. College, Columbia, MD

Vernonia lindheimeri ( Woolly Ironweed )
A perennial, reaching up to 3 x 2 feet, that is native from north central Texas to Arkansas; south into Mexico. It is most common on the Edwards Plateau in Texas. Very attractive, it should be used much more in landscaping.
Slow to establish, it won't grow much above ground during the first few years as it established its deep root systems which will enable it to survive extended drought.
The long narrow linear leaves, up to 3.2 x 0.15 inches, are bright green above, woolly beneath.
The purplish-pink flowers are borne on showy dense heads late summer through autumn.
Hardy zones 6 to 9 in full sun on neutral to alkaline, very well drained soil. Tolerates clay, extreme heat and drought making it a great plant for massing on commerical sites.
It also tolerates juglone from Black Walnuts.

'Leucophylla' ( Silver Ironweed )
An extremely attractive form with silvery-white foliage that is sold by High Country Gardens.

* excellent link found on internet
http://www.highcountrygardens.com/perennial-plants/unique-plants/vernonia-lindheimeri-leucophylla

Vernonia marginata ( Plains Ironweed )
A perennial, reaching a maximum height of 3 feet, that is native to moist soil near streams in the south central U.S. ( from central Utah to southwest Kansas; south to southeast Arizona to central Texas ). It is critically endangered in Colorado and Kansas.
The long linear leaves, up to 5 x 0.5 inches, are bright green.
The pink flower heads contain an average of 21 flowers.
Hardy zones 5 to 9 in full sun on moist, well drained soil.

* USDA-NRCS PLANTS Database

Vernonia missurica ( Missouri Ironweed )
A perennial, reaching a maximum size of 7 x 5.3 ( rarely over 6 ) feet, that is native to fertile, low meadows & prairies in midwestern North America ( from central New Mexico to southeast Nebraska to far southern Minnesota to Sarnia, Ontario to Long Point, Ontario; south to New Mexico to southern Alabama ). It is endangered in Oklahoma, Kansas, Nebraska, Iowa and Ohio; most likely extinct in Minnesota and Wisconsin. In the Windsor/Essex County, Ontario region; it was common at the Ojibway Prairie in Windsor, along Lake St Clair, at Point Pelee as well as the Lake Erie islands during the 1800s. It was also common at Detroit at that time.
The toothed, broad lance-shaped leaves are up to 8 x 2 inches in size. The foliage is deep green and woolly.
The pink flowers are borne on small heads during mid-summer to early autumn.
The stems are woolly.
Hardy zones 3 to 8 in full sun on fertile, moist soil.

* photos taken on Aug 3 2012 in London, Ontario

* photos taken on Aug 1 2018 in Ellicott City, MD

* photo taken by Robert H. Mohlenbrock @ USDA-NRCS PLANTS Database

* USDA-NRCS PLANTS Database

Vernonia noveboracensis ( New York Ironweed )
A bold, stately perennial, reaching up to 11 x 6.2 ( rarely over 6 ) feet, that is native to fertile wet thickets and marshes in the eastern U.S. ( from central Kentucky to southeast Ohio to Erie, PA to central New York State to southern New Hampshire; south to northeast Mississippi to northern Florida ). It is considered extinct in the wild in Ohio and Mississippi. In the Windsor/Essex County, Ontario region; it was known to occur on Pelee Island during the 1800s where it is now extinct. It looks great with taller ornamental grasses ( esp calamagrostis ) and taller Rudbeckia, Asters and Goldenrods. The New York Ironweed grows with horizontal rhizomes and a dense fibrous root system.
The broad lance-shaped leaves, up to 10 x 2.3 inches in size. The attractive foliage is glossy deep green.
The vivid violet-purple flowers borne in dense, large clusters, up to 2 feet across, during late summer to mid-autumn.
The flowers attract hummingbirds and butterflies.
Hardy zones 4 to 8 in full sun to partial shade on moist to wet, fertile soil. Tolerant of drought and poorly drained soil.

* photos taken on Jul 21 2011 in Columbia, MD


* photos taken on Aug 20 2011 @ Brookside Gardens, Wheaton, MD








* photo taken on July 11 2014 in Washington, DC

* photos taken on Aug 9 2020 in Columbia, MD

* photos taken on Sep 6 2020 @ Patuxent Wildlife Refuge, Laurel, MD

* photos taken on Aug 29 2021 in Columbia, MD

* photo taken on July 28 2024 in Columbia, MD

* photo taken on Aug 24 2024 @ Howard County Conservancy, Woodstock, MD

'White Lightning'
White flowers; otherwise identical to species.