Bouvardia
Bouvardia triphylla.
WINTER-FLOWERING greenhouse plants have been, with in the past few years, considerably enriched by the introduction of improved varieties of bouvardias. They are all neat-growing and free-flowering shrubs, producing delicate tubular flowers in clusters; and, though none of them should be described as massive or showy, they are invaluable, whether as, plants or as flowers, for various decorative purposes. More than this, they are particularly well suited for the green house of an eclectic amateur, for they belong to a higher range in gradations of merit than many subjects that are in general favour, and they require a little more care than the generality of plants that flower in the winter season.
Bouvardias are members of the great order of Cinchonads, and are, therefore, remarkably well connected as regards family relationships. In this order we find the trees that produce Peruvian bark, and with them such important subjects as coffee, ixora, rondeletia, manettia, gardenis, mussaenda, and ipecacuanha. Of Dr. Bouvard, curator of the Botanic Garden at Paris, there is not much known; but we find in the books a treatise on the fungi of the forest of Mormal, published at Lille, but whether by the man of science to whom the genus Bouvardia is dedicated, we cannot say.
The Cinchonads agree pretty nearly in one of their requirements. When under cultivation they need more than the average warmth of the greenhouse, many of them being true stove plants, and a few requiring the hottest place in the stove. The bouvardia is an exception so far that greenhouse cultivation suffices for it; but to enjoy its beautiful flowers in winter, something approximating to stove culture must be practised. For keeping the plants in health a temperature of 35 degree to 45 degree Fahr. suffices during winter, but we prefer to get them forward for winter flowers, and to provide for them a temperature of 50 degree to 65 degree, with a rather liberal amount of atmospheric moisture, for when thus aided they bloom with delightful freedom, and there is nothing in the winter garland under glass that can surpass them. Bouvardias may be grown from seeds and cuttings. In a garden of limited extent, propagation by cuttings alone should be practised, as it is at once certain, simple, and rapid. The cuttings should be taken from growing plants in the month of March or April, and planted firmly in sandy peat, and the process of rooting is promoted by a kindly moist heat, say a temperature of 70 degree. The best soil for them is a good turfy loam, with a reasonable addition of sharp sand; but in good peat they grow freely. In any case, strong manures are rather to be avoided than used, although we must confess that we have often aided large specimens by administering weak manure water occasionally.
In the formation of specimens, the natural growth should be humoured rather than checked; but a moderate amount of stopping to promote the formation of side shoots, and to furnish the lower parts of the plants, may be advisable. Over-potting is to be guarded against, therefore there should be no shift until the pots are well filled with roots, when the next size should be used; not, as some overhasty cultivators advocate, pots two or three sizes larger. The long rods that rise from the base indicate healthy vigour, and should not be stopped until they have attained their full length and are beginning to harden, when a moderate shortening may be performed. To regulate the flowering time of all such plants is an easy matter. It may be reckoned that from six weeks to two months will be required from the last stopping to the time of flowering, according to the season. If they are to be allowed to flower at their own time, there should be very little stopping. But if they are required to flower at a particular time, then flowering should not be allowed in advance of that time, but should be checked by careful stopping, training, and a shift into the next size of pots when the roots need it. This practice will tend to the formation of large handsome plants, but must cease entirely six to eight weeks before the time at which it is desired they shall flower. It only remains then to leave them alone, with no more shifting or stopping, keeping them warm enough and liberally supplied with water, with--if the pots are well filled with roots--weak liquid manure occasionally. There are double and single bouvardias in cultivation, all of them exceedingly beautiful. A fine half-dozen for a comfortable greenhouse are: Bridal Wreath, white, very fragrant; Queen of Roses, rosy pink; Hogarth, rosy scarlet; Dazzler, full bright scarlet; Alfred Neuner, double white; Jasminiflora, white, fine for winter.
When they are to be wintered in a cool house, bouvardias may be planted in the open ground to make free growth from June to September.