Dayflowers are greeted with delight or disdain depending on one’s personal and professional experience with the herbaceous plant.
Dayflowers are in the Spiderwort family, Commelinaceae. All family members have three-petaled flowers. Linnaeus named the dayflower genus Commelina after the surname of three botanist brothers, two were productive botanists (represented by the two larger visible petals) and the third and younger (represented by the lower smaller petal ) was lesser known.
Dayflower Description
The striking electric blue blossoms of the dayflower bloom for only one day from summer to frost. Two blue petals shaped like mouse ears stand upright. The third petal, below, is much smaller and in some species blue while in others white. Blossoms begin to wither, dissolve and vaporize by afternoon on sunlit days.
Reproductive structures emerge at the center of the three petals. Three longer white stamens contain pollen. Three shorter staminoids, sterile stamens, are tipped with cross-shaped yellow tops. The slender single white pistil is tipped in pink.
Flowers form in clusters but bloom one at a time. Each cluster is enclosed in a heart-shaped folded pale green bract called a spathe. The spathe, if pressed, releases a drop of liquid. Hence, one common name is widow’s tears. Faces of dayflowers are no larger than a square inch. Dayflowers attract bees and other small pollinators.
The leaves of dayflowers are bladelike, narrow and pointed. The veins are parallel as is indicative of monocots. Leaves are arranged alternately.
Dayflowers reproduce themselves by seed and vegetative propagation. When stem nodes touch ground, they send forth roots. Gardeners root dayflower stems in water or potting soil.
Dayflower Species in the Southeastern United States
Dayflower species common across the southeastern United States are differentiated by observing the size, shape and color of the petals, width of the leaves, growth habit and preferred habitat. Hand lens, field guide, and camera are indispensable field tools.
- C. benghalensis – Benghal dayflower, Indian dayflower, annual or perennial, introduced species native to Asia and Africa, creeping herb easily smothers farm crops, on Federal Noxious Weed List, aboveground flowers with lilac or blue petals and underground miniscule white flowers on rhizomes, reddish hairs on leaf tips, introduced in North Carolina south to Florida and west to Louisiana
- C. caroliniana – Carolina dayflower, perennial, introduced species native to India, spreading growth habit, all petals blue, found on coastal plain from North Carolina to Florida and eastern Texas
- C. communis – Asiatic dayflower, annual, introduced species native to Asia, creeping stem easily roots and forms communities, small white lower petal, common in gardens, roadsides, waste areas from Massachusetts west to Wisconsin and Nebraska and south to Carolinas and Texas
- C. diffusa – Climbing dayflower, Spreading dayflower, annual, creeping native species forming mats of groundcover, all blue petals, hairy leaf sheaths, found in bottomland, marshes, moist soils from Delaware to Kansas and southward to Florida
- C. erecta – Whitemouth dayflower, Slender dayflower, Narrow leaf dayflower, perennial, native species, erect stems, hairy leaf sheaths, small white lower petal, found in dry sandy soils from New York to Kansas and south to Florida and west to Arizona
- C. virginica – Virginia dayflower, Woods dayflower, perennial, native species, erect stems up to four feet tall, leaf sheaths edged in bristles, all petals blue, found in moist woods and shaded banks from New Jersey to Kansas and south to Florida and Texas
Dayflower Debates
Dayflowers classified as wildflowers, garden plants, pot herbs, medicinal plants, and weeds stimulate debate and discussion from those who would encourage, endure or eradicate the herbaceous plant.
The spreading growth habit of some dayflower species has led them to be classified as weedy and invasive. C. communis is named for its propensity to spread and form communities which conservationists say compete with native plants. However, some native dayflower species are being used successfully in land restoration projects because of their wandering ways.
Plant and soil studies found C. communis capable of sequestering metals like copper in its leaves. The studies suggest the plant is one potential pioneer species for land reclamation at metal mines.
The dayflower grows well in poor soil and in clay or sandy conditions giving some homeowners a groundcover for difficult areas.
Wildlife biologists report that dayflower seeds attract ground feeding doves and quail and some songbirds. Dayflower is used as one food in white-tail deer plots. C. erecta is grazed on by cattle.
Science teachers from elementary to graduate school find the C. communis leaf to be an excellent epidermal peel for the study of guard cells and stomata. Art teachers use the fragile blue petals to teach students how to make paint pigments from nature. In Japan there is a dye industry devoted to extracting the plant’s blue pigment as an artist’s paint and cloth dye.
Economic botanists note that the leaves and stems of dayflower are eaten as a potherb in Europe. The Asiatic dayflower is used in traditional Chinese medicine.
The dayflower debates will continue as sure as the dayflower continues to bloom anew each day.