Corm is a short, thick underground stem. The main function of a corm is food storage. During the growing season, the corm stores food made by the plant’s leaves. At the end of the growing season, the aboveground parts of the plant usually die, but the corm stays alive. The next spring, new aboveground stems and leaves are formed, using the food that the corm has stored all winter. A new corm then develops above the old one, and the old corm dies. The new corm continues to grow as it, in turn, stores food.
Tiny corms, called cormels, grow out of the main corm. Gardeners separate the cormels from the corm and plant them. The cormels then grow into new plants.
Corms resemble bulbs in size and shape, but their internal structure is different. Bulbs consist mainly of fleshy leaves, but a corm is mostly stem tissue, covered by thin leaves. Gladiolus and crocus are well-known plants with corms.
