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Gardenia

(named in honour of Alexander Garden, M.D., of Charlestown, Carolina, one of the correspondents of Ellis and Linnaeus). Including Rothmannia. ORD. Rubiaceae. A genus comprising about sixty species of elegant stove or greenhouse evergreen trees or shrubs, indigenous to tropical Asia, as well as the Cape of Good Hope. Flowers white, axillary or terminal, usually solitary, and generally sweet-scented; corolla funnel-shaped or salver-shaped, having the tube much longer than the calyx, and the limb twisted in aestivation, but afterwards spreading. Leaves opposite, rarely whorled. The double forms of G. florida and G. radicans produce white flowers that are amongst the most beautiful and highly perfumed of any in cultivation. Gardenias are principally grown for the use of the flowers in a cut state, as these are in great demand, and appear so much in a succession as not to render the plants sufficiently attractive by their presence for ordinary decoration, excepting that of the stove. Propagation is readily effected by cuttings. Strong, healthy ones should be selected, preferably with a heel attached, such as those obtained from the points of side shoots, half or fully ripened. Early in January is the best time to propagate for allowing the plants a long season to grow before flowering the next winter; but almost any time in the year will do when suitable cuttings can be secured. They should be inserted singly in small pots of sandy peat, unless required in large quantities, when this plan would demand too much space, and the alternative of placing several in a larger size would have to be adopted. The pots should be plunged in a bottom heat of about 75deg., in an inclosed frame of the propagating house, and allowed to remain there until the cuttings are rooted.

Cultivation. Gardenias are not difficult to cultivate, provided they have plenty of heat and moisture during the growing season, and are kept free from insects. These conditions encourage the production of strong healthy shoots, which, after being ripened, and the plants rested, supply a large quantity of flowers from the points. The young plants, when rooted, should be hardened from the frame to the open house, and potted on by liberal shifts as becomes requisite, in a lumpy compost of two-thirds peat to one of fibry loam, with an addition of some charcoal. Where bottom heat is not at command, a hotbed of fermenting material is frequently made up in a house, for plunging the pots in, the house itself being heated by pipes in the ordinary way. If carefully managed, and not allowed to over-heat, this plan is generally attended with good results. Very large plants may be obtained, under proper treatment, in one season; and if a succession is propagated occasionally to follow others, and thus some are in different stages of growth, the supply of flowers may be considerably prolonged. After the season's growth is completed, a lower temperature and more air should be given. Some persons prefer planting out Gardenias in a heated structure over hot-water pipes; but cultivating in large pots allows the advantage of being able to shift them for destroying insects and for subjecting them to lower temperatures in other houses. It is not advisable to keep old plants; much better flowers, and a greater quantity, may be obtained from young ones grown rapidly by liberal treatment each, or, at least, every second, year. Almost any amount of water may be applied to the roots in summer, and syringing morning and evening may be freely practiced. Insects. Gardenias, if not well looked after, become more infested with insects than in usual with even the ordinary occupants of warm houses. Mealy Bug is most destructive, collecting in quantities about the points, and crippling the young flowers and leaves. Careful watching for these, from the time cuttings are inserted, must be constantly kept up, and measures taken to insure their eradication if found. A wineglassful of petroleum to a three-gallon can or open pail of tepid water, thoroughly mixed, by having a syringe filled two or three times, and its contents returned into the can, previous to being applied, is one of the best insecticides. The plants should be laid on their sides, if in pots, the operation performed in dull weather, and the petroleum thoroughly removed by clean water half an hour later. This may be practiced occasionally as a preventative. Green Fly is readily destroyed by fumigation; Red Spider may be kept down considerably by syringing; and if Scale should be troublesome, they must be removed by sponging. All these infest Gardenias at some time, if the least chance is given; consequently, a watch must be kept, and measures applied, as preventatives to their becoming established.

G. amoena (pleasing). fl. white, having the lobes purple on the outside in that part which is exposed to the air, while the corolla is in aestivation, almost terminal, solitary, sessile; tube greenish, long, terete. June. l. oval, acute, glabrous, on short petioles; spines axillary, short, straight. h. 3ft. to 5ft. China. Stove. (B. M. 1904.)

G. florida (flowery).* Cape Jessamine. fl. white, sweet-scented, solitary, almost terminal, sessile, salver-shaped, nine-parted. August. l. elliptic, acute at both ends. h. 2ft. to 6ft. China, 1754. Plant shrubby, unarmed, erect. Stove. (B. M. 3349.) Of this species, there are several varieties, and that usually grown as florida is but a double-flowered variety (B. M. 2627.)

G. f. Fortunei (Fortune's).* fl. white, large, pure, fragrant. July. l. opposite, or in whorls, bright shining green. China. Apparently a very large form of the typical species. (B. R. 32, 43.) G. f. variegate (variegated). This is much the same as the type, but has leaves beautifully margined with yellowish-white. A handsome form.

G. nitida (shining).* fl. white, terminal, solitary; calyx six-parted; corolla with a narrow tube and a seven-parted, reflexed limb. October and November. l. opposite or tern, oblong-lanceolate, undulated. h. 3ft. Sierra Leone, 1844. Stove. (B. M. 4343.)

G. radicans (rooting). fl. white, solitary, almost terminal, and nearly sessile, salver-shaped, very fragrant. June. l. lanceolate. Stems radicant. h. 1ft. to 2ft. Japan, 1804. Plant shrubby, unarmed. Greenhouse. (B. M. 1842.)

G. r. major (larger).* This is one of the most profuse flowering forms; it is larger in all its parts than the type, but smaller than G. florida.

G. r. variegate (variegated). l. margined with white. Japan. An interesting and elegant form.

G. Rothmannia (Rothmann's). fl. yellow, purple; sepals subulate, rounded; tube smooth, dilated, short. July. l. oblong; stipules subulate. h. 10ft. Cape of Good Hope, 1774. Greenhouse. (B. M. 690.)

G. Stanleyana. See Randia maculata.

G. Thunbergia (Thunbergia).* fl. white, large, fragrant, terminal, solitary, sessile, eight-parted. January to March. l. elliptic, acute, glabrous, opposite, or three or four in a whorl. h. 4ft. to 5ft. Central and Southern Africa, 1774. Plant shrubby, unarmed. Greenhouse. (B. M. 1004.)