Tender herbaceous perennial plants, from South America and the West Indies, of the family Cannaceae. They have unbranched, stately stems springing from a fleshy rootstock; large, ornamental foliage; and showy gladiolus-like flowers in dense terminal clusters during summer. They are chiefly used in summer beds and borders. The origin of the name is uncertain.
Cannas can be raised from seeds but this is rarely done except for the production of new varieties. Seeds are sown in a greenhouse with a temperature of 65-70 degrees. January is the best month for sowing if it is desired to produce plants to flower the same season, but seeds may be sown in any month up to June. Before being sown, the seeds, which are very hard, are soaked in tepid water for 24 hours to hasten germination, or they are nicked with a file. They are then set 1/2 in. deep in pots filled with light, sandy soil; the soil must be kept moist. As germination is slow, the number of seeds sown should be noted, so that it may be known when all have germinated. As soon as the seedlings have formed a pair of leaves, they are potted singly in small pots, filled with a compost of equal parts loam and leaf mold, a little well-decayed manure and a scattering of sand. They are then placed in a greenhouse with a temperature of 65-70 degrees and repotted in 5- or 6-in. pots when the roots appear through the soil.
Propagation by dividing the rootstock is effected in February or March. The rootstock is carefully cut apart with as much tissue as possible to each growth bud. The divided parts are then planted in sand or very sandy soil and are placed in a greenhouse having a temperature of 70 degrees. They are kept moderately moist. When the new shoots are 4 in. long, each
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