This section is from the book "The Standard Cyclopedia Of Horticulture Vol2", by L. H. Bailey. See also: Western Garden Book: More than 8,000 Plants - The Right Plants for Your Climate - Tips from Western Garden Experts.
(bears the name of early Dutch botanists). Also written Commelyna. Commelinaceae. Day-Flower. Perennial or annual herbs, of which a very few are cultivated in the open or under glass for their interesting flowers.
Upright, spreading or procumbent, usually more or less succulent, often rooting at the joints: leaves alternate, sessile or short-petioled, clasping the stem, a If. subtending the sessile flower-cluster and forming a clasping folded spathe: flowers opening for a day, mostly blue (varying to white and rose), irregular; outer perianth parts (calyx) 3, colored, 2 of them somewhat united; inner parts (petals) 3, one of them small and 2 broad and with long claws; stamens usually 6, but only 3 of them fertile; filaments not hairy: fruit a 2-3-celled caps, on a recurved pedicel. - Nearly or quite 100 species, in warm regions around the globe, a few of them reaching cool-temperate climates. The cult, species are perennials. The hothouse species appear not to be offered in this country or to be much cultivated Allied to Trades-cantia and Zebrina.
Commelinas are mostly of easy culture, thriving well in any light rich soil. The evergreen stove and greenhouse species are readily propagated in March or April by cuttings inserted in an ordinary propagating-bed and kept close for a few days, while the tuberous-rooted half-hardy herbaceous species may be propagated either by division of the tubers or by seeds sown in a frame early in April and afterwards transplanting the seedlings in the herbaceous border. In the fall, they should be lifted and the tubers stored away in the same manner as dahlias. Of the tuberous-rooted species, C. coeles-tis is perhaps the best, its bright blue flowers being very effective, especially when planted in . masses. (Edward J. Canning.)
A. Plant hardy in the open.
Linn. (C. Sellowii, Walp. C. Sellowiana, Schlecht.). Creeping, rooting at the joints, glabrous or practically so: leaves lanceolate to ovate-lanceolate, acute or acuminate, the leaf - sheaths often ciliate: spathe-leaf acute or acuminate, broad at base, petioled: flowers few in each cluster, 1/2in. or less across, blue: caps. 3-celled and 5-seeded. N. J. southward and widely dispersed in other parts of the world. - Sometimes offered as an outdoor plant. A rose-colored form is reported.
Linn. Much like the last and often confused with it: more erect and less rooting at joints: flowers larger: caps. 2-celled and 4-seeded. N. Y. southward, and widely distributed; perhaps an introduced from Asia.
aa. Plant tender or only half-hardy.
Linn. Diffuse and branching, from a tuberous root: leaves narrow-lanceolate, 2-3 in. long: spathe-leaf cordate-ovate to lanceolate, conduplicate, more or less hairy; sheaths pubescent: flowers rich blue. Mts. of Mex. - The plant sold under this name is recommended as a free-flowering border plant in England, the tubers to be lifted in autumn and stored in dry sand for the winter.
Willd. Fig. 1042. Erect, root more or less tuberous, 10-18 in. high, branching, with clasping, long, broad-lanceolate pointed leaves and blue flowers (2-l0 together) on elongating axillary pubescent peduncles: spathe-leaf ovate, folded; sheaths ciliate. Mts. of Mex. - Runs into several forms. variety alba, Hort., has white flowers variety variegata, Hort., has flowers blue and white. C. coelestis is a half-hardy plant, in the N. requiring protection of a greenhouse, although it may be planted out. Prop, by seed, cuttings and tubers.
Fig. 1042. Commelina coelestis.
L. H. B