Houstonia caerulea  (Hedyotis c.) azure bluets Rubiaceae HECA; R (DeCandido 2001);

Hedyotis caerulea.commons.wikipedia.org

Hedyotis caerulea.commons.wikipedia.org (Accessed 4/2014).

Houstonia caerulea is a very small, delicate winter annual or perennial herb, 5-10 cm tall in flower, winter rosettes forming mats a few cm wide, colonial by slender rhizomes. 

Leaves opposite mostly basal, widest above middle, ca 1 cm long, stalk ca 1 cm; stem leaves reduced, nearly stalkless (subsessile). 

Flowers pale blue with yellow eye, to 1 cm long, 1-1.4 cm wide, radially symmetrical, tubular with spreading 4 petal lobes, ovary inferior, flowers solitary in leaf axils on stalks to 7 cm tall, styles of two different lengths (distylous), self-incompatible (Hicks et al. 1985); blooms April-June. Most likely pollinated by insects (Proctor et al. 1996). 

Fruit dry, paired capsules 0.3-0.4 cm wide, flattened, broader than long, splitting open to release minute, rounded seeds with a cavity on one side. 

Wetland status: FACU. 

Frequency in NYC: Very infrequent. 

Origin: Native. 

Habitat: A woodland plant.