Helianthus giganteus Linnaeus. Common name: Tuberous Sunflower, Swamp Sunflower. Phenology: Late Jul-Oct. Habitat: Roadsides, woodland edges, bog edges, moist thickets, ditches. Distribution: NB and ME west to MN, south to n. SC, n. GA, e. and c. TN, c. KY, n. IN, n. IL, and WI.
Origin/Endemic status: Native
Synonymy ⓘ: = C, F, FNA21, G, GW2, Il, K4, Mi, NE, NY, Oh3, Pa, RAB, S, SE1, Tat, Tn, Va, W, WV; > Helianthus alienus E.Watson — S; > Helianthus giganteus L. — S; > Helianthus validus E.Watson — S. Basionym: Helianthus giganteus L. 1753
Links to other floras: = Helianthus giganteus - FNA21
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Wetland Indicator Status:
- Atlantic and Gulf Coastal Plain: FACW
- Eastern Mountains and Piedmont: FACW
- Great Plains: FAC
- Midwest: FACW
- Northcentral & Northeast: FACW
Heliophily ⓘ: 8
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© Gary P. Fleming | Original Image ⭷
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© Gary P. Fleming | Original Image ⭷
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© Evan M. Raskin, some rights reserved (CC BY), uploaded by Evan M. Raskin source CC-BY | Original Image ⭷
© Evan M. Raskin, some rights reserved (CC BY), uploaded by Evan M. Raskin source CC-BY | Original Image ⭷
© Evan M. Raskin, some rights reserved (CC BY), uploaded by Evan M. Raskin source CC-BY | Original Image ⭷
© Evan M. Raskin, some rights reserved (CC BY), uploaded by Evan M. Raskin source CC-BY | Original Image ⭷
© Erik Danielson source | Original Image ⭷
© Gary P. Fleming | Original Image ⭷
© Richard & Teresa Ware CC-BY-NC, permission granted to NCBG | Original Image ⭷
© Andrew Lane Gibson, some rights reserved (CC BY-NC), uploaded by Andrew Lane Gibson source CC-BY-NC, permission granted to NCBG | Original Image ⭷Feedback
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Horticultural Information
Intro: Erect, rhizomatous perennial of bog edges, moist thickets and ditches.
Stems: Stems branching in upper 1/3, green or reddish-purple, rough-hairy.
Leaves: Leaves mostly alternate, petiolate, lance-shaped, 2-8 in. long, pinnately veined, with toothed or nearly smooth margins, rough-hairy above and soft-hairy beneath.
Inforescence:
Flowers: Composite flowers (heads) several in loose clusters; heads 2-3 in. wide, consisting of 10-20 yellow ray florets encircling a center disk of darker yellow tubular florets. Spreading and overlapping hairy, long, narrow bracts surround the base of each head.
Fruits: Fruit a blackish or mottled-brown, flattened, oblong achene.
Comments:
Height: 2-10 ft. (occasionally up to 13 ft.)
plant sale text:
bloom table text:
description: Erect, rhizomatous perennial of bog edges, moist thickets and ditches.
stems: Stems branching in upper 1/3, green or reddish-purple, rough-hairy.
leaves: Leaves mostly alternate, petiolate, lance-shaped, 2-8 in. long, pinnately veined, with toothed or nearly smooth margins, rough-hairy above and soft-hairy beneath.
inflorescence:
flowers: Composite flowers (heads) several in loose clusters; heads 2-3 in. wide, consisting of 10-20 yellow ray florets encircling a center disk of darker yellow tubular florets. Spreading and overlapping hairy, long, narrow bracts surround the base of each head.
fruits: Fruit a blackish or mottled-brown, flattened, oblong achene.
comments:
cultural notes:
germination code:
native range:
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