Gladioli are propagated by seeds, corms and Cormel. In each new growing season, a new corm is produced from the mother corm. Cormels are formed at the tips of branched stolons that develop from the buds located at the base of the new corm. Gladiolus can be commercially propagated by corms of at least 4-5 cm diameter. It should be healthy and disease free. Conically shaped corms are preferred over flat ones, as it gives better flowers.
The lifting of corms is carried out 6-8 weeks after harvesting of spikes. The corms should be cleaned, dipped in 0.3% Captan 50 WP for 30 min and shade-dried at an aerated place for about 15 days. Corms are then packed in crates or in net bags and should be cold-stored at 3-7oC. From cold storage, these corms should be taken out one month prior to planting and kept at ambient conditions at an aerated place. Before planting the scaly portion of the corms are to be removed and they are dipped in mancozeb 2g or Carbendazim 1g/lit of the solution.
To prepare the soil for planting, it should be spaded or ploughed to a depth of 30 cm to obtain the best flowers. The land is prepared during September – October and the corms are planted up to November. Even December planting is also recommended. To encourage sprouting, the brown dry scales or the tunics are removed. The corms should be disinfected properly before planting to reduce the chances of disease infestation. For prolonging the blooming period,
(a) planting corms of different grades,
(b) planting of corms at 15 to 30 days interval,
(c) planting of corms at different depths (7.5, 10 and 15 cm), and
(d) use of early, mid-season and late varieties, etc., are helpful. Gladiolus corms which are healthy, disease free with diameter of 4 to 5 cm should be selected and planted at a spacing of 30 x 20 cm. Shallow planting of corms is essential. The depth of planting of the corms should range from 5 to 10 cm. Deep planting of corms will result in poor production of cormels and also cause decaying of corms. Generally, the performance of high crowned corms is better than large flat corms.
FYM is mixed thoroughly in the soil while preparing the field for planting corms @ 20 tonnes/ ha of FYM. 120 kg N, 150 kg P2O5 and 150 kg K2O per hectare is recommended, of which 60 kg N and entire dose of P2O5 and K2O is applied as basal dose. The remaining N is given in two split doses, 30 and 60 days after planting. i.e. the first dose at 4-6 leaf stage and second at earthing up stage i.e. 6-8 weeks after planting.
- Central Coastal Agricultural Research Institute, Ela, Old Goa, Goa