Corms look like bulbs on the outside and often have the same protective sort of covering. They also have a central growing point where the pseudostem and/or flower will emerge and a basal plate just like that of the bulb. Bananas, Crocus, gladiolus, and freesias all grow from corms.
Corms will not show layers like a true bulb does if you cut them. The corm actually is a base for the pseudostem and/or flower stem packed with nutrients and quite solid in texture. As the pseudostem and/or flower start to grow, the corm shrivels as its nutrients are used up. The corm creates new corms either on top of or next to the desiccated ones. The corms of bananas will die once the plant blooms and produces bananas and new corms will form attached to the old corm, these new corms produce new banana plants called suckers. Because it can take 9 to 15 months for some bananas to bloom and produce fruit, it is possible for the original corm to live more than one year. This is not the case with corms that produce flowers every year; they will die once they have produced flowers. Most of your ornamental bananas will produce flowers every year. The bananas that generally bloom every year would be musa ornata varieties. The rojo banana is a variety that does not bloom are make bananas and is generally used are beautifully colors in the landscape as an ornamental banana. In a few plants, like gladiolus, the new corms may take two to three years to reach blooming size.