Tiny bluet

Houstonia pusilla, the tiny bluet or small bluet, is a delicate winter annual herb in the Rubiaceae native to open, sandy or rocky woods, glades, roadsides, and prairie edges across the south-central and southeastern United States. Plants are diminutive, only 3 to 12 cm tall, with slender, glabrous, often branched stems arising from fibrous roots. The opposite leaves are small, oblanceolate to spatulate, 4 to 12 mm long, entire, with minute stipules connecting their bases. Solitary salverform flowers, 6 to 10 mm across, terminate the slender peduncles in early spring (February to April); each flower has a four-lobed corolla varying from deep violet-blue to lavender, pale lilac, or occasionally white, with a contrasting reddish-purple to maroon eye at the throat and four short stamens. The fruit is a small, two-lobed, didymous capsule 2 to 3 mm across, splitting at the top to release minute angular seeds. The species often carpets bare patches in late winter.