Begonia

THE BEGONIA, Begonia hydrocotylifoli

TUBEROUS begonias have been discoursed upon in our Second Series, and the plant before us gives occasion for a brief essay on the species which belong more especially to the stove, and are, with very few exceptions, of no use whatever for the decoration of the open garden. By the term "stove" may be understood, in this connection, the tropical plant-house and the warm greenhouse, and it is advisable to set out with the word "stove" to impress upon the reader the fact that these begonias love warmth and moisture, and the treatment that suits many greenhouse plants will only bring disappointment if applied to them. It is a fact, however, of some importance that many of the tender begonias may be grown in an ordinary greenhouse by an expert in plant culture. A common greenhouse becomes a stove for a brief space of time, and in the course of a year a certain number of plants of good renown may be so managed that their whole season's growth may be completed by a careful management of fire-heat at first, and sun-heat afterwards, without the aid of a stove, and in a greenhouse of the most commonplace description. We have seen collections comprising many of the best species which are grown for their flowers, and the whole of the section of Begonia rex, which are grown for their magnificent leaves, brought to perfection in a common greenhouse, and the secret of success lay in the judicious timing of their growing and resting to suit the circumstances. The most important point, perhaps, is to keep them so dry in winter that frost will not prove injurious, and, on the other hand, to keep them sufficiently moist that vitality will not be impaired; for to be dust-dry is deadly to begonias, but when wintered at a low temperature they must be kept as dry as possible short of killing them by drought. One reason of their endurance in a nearly dry state with a low temperature is the bulky nature of the root-stock, which, in some sense, serves as a bulb or corm. So long as this is not frozen, and can be preserved from shrivelling, it has the power to grow when aided by warmth and moisture; therefore when wintered in a common greenhouse the tender begonias require to be started into growth in spring on a steady hotbed, or in the sunny corner of a greenhouse, where they can be a little shaded and have careful watching, until the growth and the season have both advanced to render such special cares no longer necessary.

A code of culture for the more tender begonias may be given in a few words. They are easily propagated, as they root freely in sandy soil with the aid of heat and moisture, and at this stage must be treated as stove plants. The soil that suits them best is mellow sandy loam enriched with clean leaf-mould, and with the pots well drained as a protection against stagnant moisture. They grow fast and require rather liberal pot-room, but it is good practice for the amateur always to keep plants in the smallest pots consistent with healthy growth and free development, for the commonest mistake of beginners is to provide more pot-room than the roots can fill in a reasonable space of time, this resulting in souring of the soil and an arrest of growth altogether. They must be shifted on as necessary, and robust kinds must have larger pots than weak kinds, while the soil must always be rather light and good without any animal manure. A little stopping and training may be necessary in certain cases, but the less the better, free natural growth being best for displaying the real beauties of the plants. Every sort will flower at its own season, unless the management is such as to thwart its purpose. When grown in a common greenhouse, winter flowers are not to be looked for; but with a temperature of fifty to sixty degrees through the winter, the stove begonias will give a fine crop of winter flowers; and as young free-growing plants always flower best, a fresh stock should be raised every year, and old plants should be destroyed.