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Some plants, such as tulips, daffodils, and onions, grow from bulbs. Others, such as crocosmia, gladiolus, and taro, grow from corms. And then there are tuberous plants, such as potatoes, dahlias, and begonias. These are the most common underground storage organs in plants.
How do I distinguish between them?
Bulbs are plant storage organs generally grown underground, consisting of a short stem (the basal plate), from which grow overlapping, swollen leaves or leaf bases. The top growth emerges from the bulb center. Here's an example:
Corms are not made up of leaves, but a vertical swollen compact stem, and as such are solid. The corm is protected by a tunic of old leaf petioles. Here's an example:
Tubers are, simply, enlargements in the underground stem or lateral root of a plant that are used for food storage. These vary greatly in appearance, but all have the same function. Here's an example:
