The bulbous plants are divided into two categories i.e., hardy and tender bulbs. The hardy types can be left in the ground and are separated after 2-3 years for their multiplication (e.g. Amaryllis, tuberose, canna, zephyranthes, crinum, etc.). On the contrary, the tender types cannot be left in the ground after flowering and are to be lifted from the ground on maturity. After their treatment against diseases, these are to be stored in cold storage or cool places during off season for next year planting e.g. Gladiolus, Narcissus, Daffodils, Freesia, Dahlia, etc.
The following are the common methods employed for propagation of bulbous plants;
Lifting of bulbs and their storage
Tender bulbs like Gladiolus, Dahlia, Narcissus, Daffodils, etc. are to be dug from the soil 10-12 weeks after flowering has been finished. Before lifting the bulbs, water is withheld. After digging, bulds are dried in shade for few days. Then these are treated with 0.2% Bavistin solution for 30 minutes and thereafter stored. Hardy bulbs are separated after 2-3 years and are again planted in the planting season.
Begonia sp. (Begoniaceae)
Begonias are grouped into three main classes according to root types i.e. rhizomatous (Begonia red), tuberous (B. tuberhybrida) and fibrous (B. semperflorens). Out of three types rhizomatous and fibrous rooted are grown in the plains whereas tuberous rooted can be grown successfully in hills. The important varieties of rhizomatous begonia are: Peace Majesty Silver Queen, Emperor Mikado, Can Can, Crimson Glory, Black Knight, Curly Star Dust, Dew Drop etc. The important varieties of fibrous rooted are: Goldilock, Bo-peep Little Gem, Ballet, Lady Frances, Pink Jewel, Flamengo, Cindrella, Charm, Silver Star, Pink Camellia etc. The tuberous rooted begonias are valued for their attractive flowers and are grouped into Rose form, Camellia flowered, Carnation flowered, Daffodil flowered or Picotee.
Canna indica (Cannaceae)
Canna is a rhizomatous plant and is very easily propagated by dividing the rhizomes into 10-15 cm pieces during end of June.
Dahlia: Dahlia variables (Compositae)
Propagation of dahlia is done by seeds, division of tubers and terminal cuttings. The propagation through seeds is easy and the best way to achieve striking mixtures of colourful flowers which are sown in September-October. The varieties which are being marketed in India are Giant Exhibition mixed, Dwarf Double Red Skin, Coltners hybrids, and Border Jewels, Rigoletto, and Citation. Tubers are stored during summer in cool place or in refrigerator. After careful separation, tubers are planted directly in field in August. The care with a vegetative bud. The terminal cutting should be solid and made in September-October from plants and after treatment with seradix-I are planted in sand. It takes about 2-3 weeks for rooting and after that they are transplanted inpots (25-30cm) or in beds.