Trichostema dichotomum Linnaeus. Section: Trichostema. Common name: Common Blue Curls. Phenology: Aug-Nov. Habitat: Dry woodlands, longleaf pine sandhills and dry flatwoods, disturbed areas, roadsides, thin soils around rock outcrops. Distribution: ME, ON, QC, MI, and IA, south to c. FL and TX.
Origin/Endemic status: Native
Synonymy ⓘ: = Ar, C, Il, Mi, Mo3, NcTx, NE, NY, Pa, RAB, S, Tat, Tn, Tx, Va, W, WV, McClelland & Weakley (2019) in Weakley et al (2019a); = Trichostema dichotomum L. var. dichotomum — G; < Trichostema dichotomum L. — Fl6, K4, WH3; > Trichostema dichotomum L. var. dichotomum — F; >< Trichostema dichotomum L. var. puberulum Fernald & Griscom — F; Trichostema dichotomum L. — (basionym)
Wetland Indicator Status:
- Atlantic and Gulf Coastal Plain: UPL (taxonomic split from wetland indicator species)
- Eastern Mountains and Piedmont: UPL
- Great Plains: FAC (taxonomic split from wetland indicator species)
- Midwest: UPL (taxonomic split from wetland indicator species)
- Northcentral & Northeast: UPL (taxonomic split from wetland indicator species)
Heliophily ⓘ: 8
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Horticultural Information
Intro: Erect annual found in dry woodlands, disturbed areas and thin soils around rock outcrops.
Stems: Stems 4-angled, branched, hairy and with abundant long-stalked glands.
Leaves: Leaves opposite, petiolate to sessile, elliptic and bluntly pointed, 1/2-2 1/2 in. long, minutely hairy and glandular.
Inforescence:
Flowers: Flowers in a terminal panicle, with 2 leaf-like bracts at the base of each 1- to 3-flowered stalk; dark blue to purple; about 1/2 in. long; bilaterally symmetric; consisting of 5 spreading lobes, the 4 upward-pointing ones similar in size and shape, and the longer downward-pointing one with a blue-purple-spotted white patch; 4 long stamens curl above.
Fruits:
Comments:
Height: 1-2 ft.
plant sale text: Forked bluecurls is a delicate annual that is covered with small but elaborate blue-purple flowers. Its common name refers to the long stamens that curl over at the top of the flower. Blooming late summer to fall, this species produces many flowers over the course of the season, though each flower lasts less than a day. Trichostema dichotomum is in the mint family and is attractive to pollinators, especially native bees. Forked bluecurls readily self-sows, though does not like competition,so give it a little space and you may be rewarded with a bountiful stand of forked bluecurls.
bloom table text:
description: Erect annual found in dry woodlands, disturbed areas and thin soils around rock outcrops.
stems: Stems 4-angled, branched, hairy and with abundant long-stalked glands.
leaves: Leaves opposite, petiolate to sessile, elliptic and bluntly pointed, 1/2-2 1/2 in. long, minutely hairy and glandular.
inflorescence:
flowers: Flowers in a terminal panicle, with 2 leaf-like bracts at the base of each 1- to 3-flowered stalk; dark blue to purple; about 1/2 in. long; bilaterally symmetric; consisting of 5 spreading lobes, the 4 upward-pointing ones similar in size and shape, and the longer downward-pointing one with a blue-purple-spotted white patch; 4 long stamens curl above.
fruits:
comments:
cultural notes:
germination code: 5
native range: eastern North America