3.
Portulaca grandiflora
Hooker, Bot. Mag. 56: plate 2885. 1829.
Moss-rose
Plants
annual; roots fibrous.
Stems
prostrate to suberect; trichomes conspicuous at nodes and in inflorescence; branches to 30 cm.
Leaf blades
linear to lanceolate, terete to hemispheric, 5-30 × 1-5 mm, apex acute or subacute; involucrelike leaves 8-9(-14).
Flowers
25-55 mm diam.; petals pink, red, purple, yellow, bronze, or white, obovate, 15-25 × 15-20 mm; stamens 40 or more; stigmas 5-8.
Capsules
ovoid, (3.5-)4-6.5 mm diam.
Seeds
steely gray, often iridescent, orbiculate or elongate, flattened, 0.75-1 mm diam.; surface cells obscurely stellate with tubercles mostly abaxially.
2
n
= 18.
Flowering late spring-fall. Sandy soils; 0-2000 m; introduced; Ont.; Ala., Ariz., Ark., Calif., Colo., Conn., Del., D.C., Fla., Ga., Ill., Ind., Iowa, Kans., Ky., La., Md., Mass., Mich., Minn., Miss., Mo., Nebr., Nev., N.H., N.J., N.Mex., N.Y., N.C., N.Dak., Ohio, Okla., Pa., R.I., S.C., S.Dak., Tenn., Tex., Vt., Va., W.Va., Wis.; South America; naturalized in Europe.
Portulaca grandiflora
is naturalized in gardens and has escaped to roadsides and waste places. Studies of seed surfaces from specimens representing 100 years of collections with distribution over the United States show remarkable consistency in seed morphology. Tubercles may extend onto the lateral surface, where they are widely scattered. Only one specimen was found with no tubercles at all.
