Clerodendron
(from kleros, chance, and dendron, a tree; said to be owing to the uncertainty of the medicinal qualities). SYNS. Ovieda, Siphonantha, Volkameria, and Volkmannia. ORD. Verbenaceoe. A genus containing about seventy species of mostly stove or greenhouse ornamental plants, having terminal panicles of brightly coloured pentamerous flowers, with exserted stamens and style; and simple leaves. These are among the best of stove plants, and in habit of growth present two sections, one with a climbing habit, and the other shrubby. A mixture of equal parts peat and loam, with the addition of a little leaf mould or decomposed manure, and some charcoal or sand, suits the climbing ones admirably. The shrubby sorts have more gross foliage, and need something stronger to enable them to throw up their large panicles of rich scarlet and other coloured flowers. They should be cut close back soon after flowering, and be kept somewhat dry during the winter, in a temperature of about 55deg. Propagation is very easily effected. Cuttings of the shrubby sorts, put in when the plants are cut down, root readily. Pieces of the stem, or side branches, from 3in. to 6in. or more in length, should be inserted in sandy soil, watered, and then plunged in a bottom heat of 70deg. Clerodendrons may also be propagated by seed, which, if sown when ripe, or in the spring, and grown on in heat, may be converted into flowering plants the second season. The climbing varieties do not root quite so readily from cuttings as the other section; but cuttings of the ripened wood, when the plants are pruned after flowering, should be put in sandy soil, and covered with a bell glass. Clerodendrons are subject to mealy bug, but not more so than many other stove plants. The best cure for this pest is constant attention by hand-pickings, and washing with soft soap water or an insecticide. By such means, it may be readily kept in check, though rarely absolutely destroyed. Aphides sometimes attack the young and tender shoots; these may be destroyed, as soon as detected, by fumigating, two evenings in succession--not too strongly, or injury may be caused.
As the plants shed their leaves, little or no water will be needed during winter, but they should not be kept in too low a temperature. In January or February, they should be started in a brisk heat. When those in pots have grown a few inches, they should be shaken out, and potted in fresh soil. If they can be plunged in bottom heat for a time, they will thrive all the better and grow faster. Of course, climbing Clerodendrons, planted out in the stove, cannot be removed into a lower temperature; but the stove may be kept cooler in winter--say, a minimum temperature of 60deg.--and, as the wood has grown so near the glass, it will generally be sufficiently ripened to flower well the succeeding season. C. Thomsonoe is one of the most distinct and useful of stove climbers, and is also a good exhibition plant when well grown in a large pot. C. fallax is one of the best shrubby species.
C. Bethuneanum (Capt. Bethune's).* fl. crimson, with a white spot on the upper, and a purple one on the two lateral lobes; panicles large, terminal, pyramidal; bracts, pedicels and calyces all coloured. l. large, cordate-acuminate, smooth above. h. 10ft. Borneo, 1847. Stove shrub. (B. M. 4485.)
C. Bungei (Bunge's). A synonym of C. foetidum.
C. calamitosum (calamitous). fl. white. August. h. 4ft. India, 1823. Stove. (B. M. 5294.)
C. fallax (deceptive). fl. bright scarlet; panicles terminal, erect, many-flowered. August and September. l. large, cordate-ovate, slightly lobed, dark green. Java. An erect-growing stove shrub.
C. foetidum (foetid).* fl. lilac-rose, in dense terminal corymbs. August. l. large, pubescent, cordate-acuminate, toothed, on slender petioles. h. 5ft. China, 1820. A handsome greenhouse or nearly hardy shrub, armed with short rigid prickles. SYN. C. Bungei. (B. M. 4880.)
C. fragrans (fragrant).* fl. white; corymb terminal, hemispherical, compact. August to December. l. sub-cordate, serrate, pubescent, with two glands at the base. h. 6ft. China, 1790. Greenhouse. (B. M. 1834.)
C. f. flore-pleno (double-flowered).* fl. white, suffused with pink, very fragrant, disposed in compact heads. October. l. roundish-ovate or obovate, quite entire. h. 6ft. China, 1790. Greenhouse shrub.
C. hastatum (spear-leaved). fl. white, very fragrant, produced in a large panicle. June. l. large, halbert-shaped. h. 6ft. India, 1825. Stove shrub. (B. M. 3398.)
C. infortunatum (unfortunate). fl. vivid scarlet, large, disposed in coloured panicles. l. roundish-cordate, glossy dark green. h. 6ft. Ceylon. Stove shrub, very ornamental when in flower. (B. R. 30, 19.)
C. myricoides (Myrica-like). fl. white, blue, disposed in fascicled axillary cymes. Spring. l. oblong-lanceolate or obovate, toothed. Tropical Africa. A dwarf stove shrub. SYN. Cyclonema myricoides.
C. paniculatum (panicled). fl. scarlet, disposed in a large pyramidal terminal panicle. August. l. large, long-stalked, cordate-hastate, lobed at the margin, and somewhat shiny above. h. 6ft. Java, 1809. A very handsome stove shrub. (B. R. 406.)
C. scandens (climbing).* fl. white; corymbs many, axillary, and terminal. August. l. cordate-ovate, acuminate, entire. Plant downy; stems tetragonal, scandent. Guinea, 1822. Stove. (B. M. 4354.) C. serotinum (late). fl. pure white, sweet-scented, produced in large corymbose panicles, 1ft. or more across; calyx rose-coloured, angular. l. cordate, decussate, h. 10ft. China, 1867. A much-branched greenhouse or half-hardy shrub. (R. H. 1867, 351.)
C. Siphonanthus (siphon-flowered). Tube Flower. fl. white. h. 6ft. India, 1796. Stove. SYN. Siphonanthus indica.
C. speciosum (showy).* fl. rich deep rose; calyx large, suffused with red. l. oblong-ovate, glabrous. A very ornamental climbing hybrid. (I. H. 593.)
C. splendens (splendid).* fl. scarlet; panicle terminal, corymbose. June, July. l. oblong, wavy, acuminated, rather cordate at base Sierra Leone, 1839. Stove climber. (B. R. 28, 7.)
C. s. speciosissima (showiest).* fl. bright scarlet, disposed in panicles. Summer. l. somewhat oblong, of a deep shining green. A very handsome form of the foregoing species, and one of the best stove climbers grown.
C. squamatum (scaled).* fl. bright scarlet, produced in large coloured branching panicles. Summer. l. roundish-cordate. h. 10ft. China, 1790. A very fine stove shrub. (B. R. 8, 649.)
C. Thomsonae (Mrs. Thomson's).* fl. bright crimson, disposed in large panicles; calyces pure white. l. ovate, acuminate, smooth, dark green, opposite. h. 12ft. Old Calabar, 1861. On account of the brilliant colour of its flowers, and the freedom with which they are produced, this is the most widely grown stove climber of the genus. (B. M. 5313.)
C. trichotomum (three-forked). fl., calyx red, inflated; corolla white; cymes loose, terminal, long-stalked, trichotomously-branched. September. l. stalked, ovate, tapering at both ends, serrate. h. 6ft. Japan, 1800. A very handsome hardy shrub. (B. M. 6561.) C. viscosum (clammy). fl. white, with flesh-coloured centre; calyx large, five-cornered, viscid; segments of corolla nearly equal, the uppermost a little the largest, irregularly disposed, looking all upwards, leaving a wide space between two of them. May to August. l. cordate, toothed. Somewhat downy. h. 6ft. India, 1796. (B. M. 1805.)