Impatiens Balsamina. Half-hardy annual
The older methods of growing Balsams prescribed a false system, comprising disbudding, stopping, and other interferences with the natural growth of the plant. The rule of pinching back the leader to promote the growth of side shoots, and removing the flower buds to increase the size of the plants, was altogether vicious, because the natural growth is more elegant and effective. The finest flowers are produced on the main stem, and these are completely sacrificed by disbudding.
It is desirable to make two or three sowings of Balsam, say from the middle of March to the middle of May, the earlier sowings to be put on a sweet hot-bed, although March sowings will soon germinate in a frame, and the May sowing may be made in the open ground on a prepared bed. The soil at every stage should be rich and light, but not rank in any degree. Prick out the plants from the seed-pans directly the first rough leaves show, and soon after shift them again to encourage a stout dwarf habit. A sunny position should be chosen for the bed, in which they may be planted out about the first week of June, or earlier if the weather is particularly favourable. Heat, moisture, and a strong light favour a fine bloom, and, therefore, water must be given whenever dry weather prevails for any length of time. If kept sturdy while under glass, they will need no support of any kind, and although they are peculiarly fleshy in texture, it is seldom they are injured, even by a gale. When grown in pots throughout, the chief points are to shift them often in the early stages, to promote free growth in every reasonable way, and to cease shifting when they are in pots sufficiently large to sustain the strength of the plants. Generally speaking, eight-inch pots will suffice for very fine Balsams, but ten-inch pots may be used for plants from an early sowing. They will probably not show a flower-bud while increased pot room is allowed them; but as soon as their roots touch the sides of the pots the bloom will appear. It is occasionally the practice to lift plants from beds when pot Balsams are wanted. This method has the advantage of being the least troublesome, and as the plants need not be lifted until the flowers show, favourite colours can be chosen.
BEGONIA, TUBEROUS-ROOTED
Begonia hybrida. Half-hardy perennial
One of the most remarkable achievements in modern horticulture is the splendid development of single and double Tuberous-rooted Begonias from the plant as first introduced from the Andes. Originally the flowers were small, imperfect in form, and deficient in range of colour. But experts were quick in apprehending the capabilities of this graceful plant, and it proved to be unusually amenable to the hybridiser’s efforts. Now the large symmetrical blossoms of both single and double flowers challenge attention for beauty of form and an almost endless variation of tints peculiar to the Tuberous-rooted Begonia. The plants are conspicuous ornaments of the conservatory and greenhouse for several months, and experience has proved that they make unique bedders, enduring unfavourable conditions of weather which are fatal to many of the older bedding subjects.
From the best strains of seed it is easy, with a little patience, to raise a fine stock of plants, possessing the highest decorative qualities. Under generous treatment the seedlings from a January or February sowing come into bloom during July and August. The seed should be sown in well-drained pots containing a good compost at the bottom, with fine sandy loam on the surface, pressed down. Before sowing sprinkle the soil with water, and sow the seed evenly, barely covering it with fine earth. A temperature of about 65° is suitable. Germination is both slow and irregular, and the plants must be pricked off into pans or small pots as fast as they become large enough to handle. This process should be followed up so long as seedlings appear and require transferring. They may be shifted on as the growth of the several plants may require. Begonias need more attention with reference to an even temperature during this stage than at any other period.
The merits of Begonias as bedding plants are now recognised in many gardens, and they deserve to be still more widely grown. It is wise to defer planting out until June. In the open ground they produce abundant supplies of flowers for cutting at the end of September and early in October, when many other flowers are over. The plants should be put out when they show themselves sufficiently strong, and it is better to be guided by the plants than by any fixed date. The beds must be freely enriched with well-rotted manure and decayed vegetable matter; it can scarcely be overdone, for Begonias are gross feeders.
The earliest plants to flower will often be retained in the greenhouse, as they follow in succession the Cinerarias and Calceolarias. Those that start later may be turned out as they come into bloom, which will probably be in June. By deferring the planting out until there is a show of bloom a selection of various shades of colour is possible, and this will greatly enhance the beauty of the beds. Begonias are hardier than is generally supposed; they need no protection, and require no heat, except in the stage of seedlings, when first forming their tubers.
For autumn decoration Begonias should be taken up from the beds during September and potted, when they will continue to bloom in the greenhouse or conservatory for a considerable time, and form a useful addition to the flowering plants of that period.