Corm

Taro corms for sale in a Réunion market

A corm is a short, vertical, swollen underground stem of a plant (usually one of the monocots) that serves as a storage organ to enable the plant to survive winter or other adverse conditions such as summer drought and heat (estivation). A corm consists of one or more internodes with at least one growing point, and is typically surrounded by protective skins or tunics. Inside, a corm is mostly starch-containing parenchyma cells. Corms can be dug up and used to propagate or redistribute the plant (see, for example, taro).

Externally, they are often similar in appearance to bulbs, and erroneously called by that name, but internally their solid tissue easily distinguishes them from bulbs, which are visibly layered.

Cultivated plants that form corms include:

• Many plants of the family Iridaceae grown for their flowers, including Crocus, Gladiolus, Iris, and Montbretia
• Many plants of several families grown as root vegetables; see that article for a list.

See also

• Rhizome
• Tuber
• Root vegetable