Plant out when all danger of frost is past, in muck if possible, or in heavily manured loam; the more freely they are watered the finer will be the growth. Old bulbs should give leaves three feet or more in length and correspondingly wide.
Single specimens are fine in pots, vases, or tiles, but they are really seen at their best in large clumps on the lawn, or edging beds of Cannas or other subtropical plants.
They are easily wintered and multiply very rapidly; and, as much better effects can be obtained by planting largely of one variety, an effort should be made to have a generous supply. Aim for a tropical luxuriance of effect—whether the plants used are Cannas, Caladiums, Ricinus, or all three.
Tuberous Begonias should be started at the same time as the Caladiums, Cannas, and other tuberous plants. Pot singly in small pots of leaf-mould, setting the tuber level with the surface of the earth, but shaping the soil away from it toward the edge of the pot that water may not settle around it. The side showing a slight depression is the top. Often it is difficult to determine this, in which case the bulb may be laid on the surface until growth begins and the fact can be determined, when it may be potted. Do not keep too warm, as that induces a leggy growth; a temperature of about 60° is right.
Bed out, when all danger of frost is past, in partial shade. In England it is claimed that they will stand the hottest sun, but the atmosphere of England is very different from our dry air, and the tuberous Begonia does better with us if shaded. Where there is no natural shade an awning of cotton cloth during the hottest part of the day answers every purpose. Gloxinias are started the same as tuberous Begonias and require practically the same treatment, but more heat. Fuller cultural directions are given in the chapter on growing from seed.
Fancy-leaved Caladiums, though belonging to the same family as C. esculentum, bear little resemblance to that sturdier branch, being small in growth, gorgeous in colouring, and exceedingly delicate. Unlike the Crotons and Coleus, which revel in full sunshine, they develop their beautiful colours best in partial or complete shade. They do, however, love a warm atmosphere and must be guarded against sudden chills and draughts. They are very desirable for window-boxes on the north side of the house, for growing in sheltered nooks, and for warm, sheltered positions on porches. Several may be grouped together in a ten-inch pot very effectively, as they require but little room. They may be brought inside in the fall, and kept growing until they show signs of resting, when water should be gradually withheld until the leaves have ripened. The pots should then be set away in a warm, dry place—as a shelf in a closet—until wanted the following spring.
Such wonderful things have been accomplished in Gladiolus culture that one scarcely recognises the old favourite. All along the line, size, colour, texture, markings show the effect of a high state of cultivation and careful hybridising. The Childsi are, perhaps, the finest; while several of the strains of giant Gladiolus show wonderful size and colour. They increase rapidly, and one should buy a few bulbs each year so as to maintain a high standard.
When ready to plant, remove all loose husks, dead roots, and stalks, leaving the bulb clean and fair. Plant directly in the open ground, sufficiently late for frost to have gone by the time they are up. Plant the bulbs eight inches deep in fine leaf-mould, or a mixture of muck, loam and old manure, or even well-enriched garden loam. Planted deeply they will not need staking—an important point in growing Gladioli; nor will they be so much affected by cold, heat, or draught as in the case of shallow planting, and may be planted earlier and left much later in the fall, giving the bulbs more time to ripen.
They should be cultivated frequently during the summer or well mulched and supplied with water as needed. No seed should be allowed to form, as the plants make new bulbs each year, sometimes several, and that, with the production of flowers, is enough for one plant. A plant that seeds freely will not produce as many or as good bulbs. Take up in the fall before the ground begins to freeze, and put in a warm, sunny place for a few days to dry. Remove the stems by cutting off six or eight inches above the bulb, but do not attempt to pull or break them, as that will injure the new shoot which lies just inside the old stalk. Tie in bunches and hang in a dry, cool place, free from frost, or store in paper sacks.
Montbretias resemble the Gladioli in flower and foliage, but are very slender of growth. They throw long, graceful sprays of brilliant scarlet, orange, and lemon, very desirable for cut flowers. The flowers open successively, as do the Gladioli, and are in bloom a long time. They may be grown in the corners of the Gladiolus bed with good effect. The culture is the same, except that the Montbretias are not planted so deeply—about three inches. They multiply very rapidly—about fourfold, and are as easily cared for as the Gladioli.