This section is from the book "Nature's Garden", by Neltje Blanchan. Also available from Amazon: Nature's Garden; An Aid To Knowledge Of Our Wild Flowers And Their Insect Visitors.
Flowers - From blue to purple, with a yellow centre; a Western variety, white; usually several buds at the end of stem, between 2 erect unequal bracts; about 1/2 in. across; perianth of 6 spreading divisions, each pointed with a bristle from a notch; stamens 3, the filaments united to above the middle; pistil 1, its tip 3-cleft. Stem: 3 to 14 in. tall, pale hoary green, flat, rigid, 2-edged. Leaves: Grass-like, pale, rigid, mostly from base. Fruit: 3-celled capsule, nearly globose.
Flowering Season - May - August.
Only for a day, and that must be a bright one, will this "little sister of the stately blue flag" open its eyes, to close them in indignation on being picked; nor will any coaxing but the sunshine's induce it to open them again in water, immediately after. The dainty flower, growing in dense tufts, makes up in numbers what it lacks in size and lasting power, flecking our meadows with purplish ultramarine blue in a sunny June morning. Later in the day, apparently there are no blossoms there, for all are tightly closed, never to bloom again. New buds will unfold to tinge the field on the morrow.
Usually three buds nod from between a pair of bracts, the lower one of which may be twice the length of the upper one; but only one flower opens at a time. Slight variations in this plant have been considered sufficient to differentiate several species formerly included by Gray and other American botanists under the name of S. Bermudiana.