This section is from the book "A Guide To The Wild Flowers", by Alice Lounsberry. Also available from Amazon: A Guide to the Wild Flowers.
Mint.
Blue, turning to purple.
Fragrant.
Mass. to Florida and westward.
Late summer and autumn.
Flowers: single; axillary, or in raceme-like clusters at the ends of the branches. Calyx: tubular; five-cleft. Corolla: two-lipped; five-divided; the upper lobe deeply cleft. Stamens: four; curved; exserted with hairy filaments. Pistil: one; style, two-lobed. Leaves: opposite, on short petioles; lanceolate; entire; rather clammy. Stem: branching; clammy.
Blue curls does its best to be agreeable and throws out an abundance of bloom in the late summer. It is not, however, very pretty, and it is to be doubted whether its fragrance is wholly agreeable. The common name refers to its hair-like curling filaments.
 
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