Coleus
(from koleos, a sheath; in allusion to the filaments being connected, and forming a tube at the base, which sheathes the style). ORD. Labiatae. A genus of stove herbs, annual or perennial at the base, rarely suffruti-cose. Whorls usually six-flowered, but often many-flowered, sometimes very dense, and sometimes loose, cyme-formed. The monadelphous stamens distinguish this genus from all others of the order. The foliage of the hybrid varieties and sports of Coleus are unsurpassed for beauty of colour; and, whether grown as large or small plants, they are extremely useful for decorative purposes. Their culture is very simple, but unless a minimum temperature of 55deg. is maintained, they cannot be wintered safely. Where such conditions do not obtain, it is better to purchase plants in spring, grow them on for the season, and then throw them away.
Coleus thrive well in a compost of one-half rotten turf, obtained from an old pasture, one-fourth thoroughly rotted cow manure, and the remainder of sharp sand and leaf soil in equal proportions. Pot moderately firm, and water freely when growth has commenced, giving occasional doses of liquid manure when established, especially during hot weather, as the plants then grow very rapidly. Plenty of air and light must be afforded in summer, in order to keep the plants strong and short-jointed. Care must also be taken that they do not suffer for want of water, or the lower leaves will drop off, and thus render them unsightly. Coleus grown for exhibition should be of globular or pyramidal form, with the lower leaves covering the edge of the pot, so that neither bare stems nor soil are visible. When grown for ordinary decoration, useful plants may be obtained, and the colours in the leaves more highly developed, by cultivating in comparatively small pots. Those of 5in. or 6in. diameter are large enough to produce good-sized plants that are indispensable for greenhouse or any indoor decorations in summer and autumn. Being of quick growth, and very easily propagated, the loss of a Coleus when used in decorating is of little consequence, compared with the majority of other plants. The flowers of the foliage kinds are insignificant, and the spikes, when seen, should be pinched out. The cultivation above recommended also suits the green-leaved species; but, after a few pinchings, to secure bushy plants, they should be allowed to develop their flowers, some of which are highly ornamental. Cuttings strike with the greatest freedom at almost any time of the year, and, with a good moist heat, will quickly form fine specimens. They are best placed separately in small pots, and, when rooted, may be potted on, allowing a liberal shift each time. Coleus may also be increased by seed; but this method is only adopted for raising new varieties. C. Verschaffeltii, a variety of C. Blumei, is much grown for bedding purposes, and is especially employed in large carpet-bedding designs; it is one of the most effective crimson-leaved subjects for the purpose, and, arranged with Centaurea or Golden Feather, is very striking.
C. barbatus (bearded). fl. brownish, with the lower lip nearly ovate, compressed, and hairy; racemes terminal. November. l. oval, scalloped, downy and wrinkled, gradually narrowed into the footstalk. Stem quadrangular. h. 2ft. Abysinnia. Perennial. Every part of the plant has a powerful fragrance. (A. B. R. 594.) SYN. Plectranthus barbatus.
C. Blumei (Blume's). fl. white and purple, disposed in a terminal elongated whorled spike or raceme. l. rhomboidal ovate, membranous, deeply and coarsely inciso-serrate at the margin, the apex acuminate, entire as well as the base; yellowish-green in colour, the whole disk dark purple or sanguineous, breaking into spots near the margin. h. 1ft. to 1 1/2ft. Java. Perennial. It is from this species that the innumerabe variegated forms (so extensively grown for decorative purposes) including Verschaffeltii, have originated. (B. M. 4754.) C. Colvillei (Colville's). A synonym of Plectranthus coleoides. C. inflatus (inflated). fl. lilac, disposed in compound, subracemose spikes. December. l. on long petioles, opposite, ovate, sharply acuminated, very coarsely serrated. Stems and branches square; the base of the stem scarcely woody, often tinged with orange-colour and spotted with red. h. 3ft. Ceylon. Perennial. (B. M. 5236.) C. Macraei (Macrae's). fl. variegated with white and dark purple, disposed in a large terminal panicle; corolla very curious in the sudden geniculation near the middle of the tube, in the ample and compressed throat, and especially in the large boat-shaped lower lip. Summer. l. ovate, acuminate, serrated, dark green above, beneath deeply purple, as are the petioles. Stems quadrangular, dark purple, branched, with opposite branches. h. 2ft. to 3ft. Ceylon, 1852. Perennial. (B. M. 4690.) C. scutellarioides (Scutellaria-like). fl. blue, with the lower lip white and quadrifid; disposed in verticillate racemes. l. lanceolate-ovate, serrate, light green above, underneath brownish, as is also the stem. East Indies, North Australia, &c. A tall herb or under-shrub. SYN. Ocimum scutellarioides. (B. M. 1446.) The varieties of this genus are innumerable, and a number are added each year. The following is a selection of the best kinds now in cultivation; the descriptions refer to the leaves:
ADA SENTANCE, highly coloured, good; ALLEN CHANDLER, light crimson, self-coloured, good; DISPLAY, bright magenta-crimson, blotched bronze, broadly margined with green; DUCHESS OF EDINBURGH, very dark, margined and blotched with magenta; EDITH SENTANCE, large, blotched crimson, green edge, showy; H. A. MANN, creamy-white, tinted rosy-pink; HARRY VEITCH, pale crimson and yellow, crimpled foliage; JAMES BARNSHAW, good; J. F. PAWLE, crimson, pale yellow margin; KENTISH FIRE, purplish-crimson, much divided, good; LADY BURRELL, extra fine; MISS ROSINA, magenta-crimson and yellow, highly coloured; MISS SIMPSON, extra fine; MR. G. SIMPSON, dark velvety crimson, self, one of the most distinct and best; MRS. SHARMAN, irregularly marked, yellow and crimson; MRS. STEDDALL, vivid crimson and pale green, small, fine and showy; MRS. VAUGHAN, dark crimson, broad band of pale yellow; PICTUM, small, deeply cut, pretty; PILLAR OF GOLD, much divided, yellow, tinted rose; POMPADOUR, large, prettily mottled with many colours, very distinct and good; RENOWN, light green, reticulated and irregularly mottled with dark maroon; SHAH, rose-crimson and yellow, broad, good; SUNBEAM, green, veined yellow, distinct.