Many plants are called bulbs, but not all are true bulbs. Bulblike plants include corms, rhizomes, tubers and tuberous roots.
– All are small, self-contained factories that contain everything needed to produce a plant and a flower. The bottom is known as the basal plate and contains the roots.
– True bulbs are short underground stems surrounded by modified fleshy leaves, called scales, that protect and store food for use by the plant embryo. Plants with true bulbs include daffodils, hyacinthsand alliums.
– In corms, the food is stored in an enlarged basal plate rather than scales. Common plants with corms include gladioluses and crocuses.
– Rhizomes, such as those of irises and cannas, are thickened, elongated stems that grow partially or entirely beneath the ground.
– A tuber is a swollen, underground stem base similar to a corm, but there is no basal plate and roots grow from all sides.
– Tuberous roots come with plants such as begonias, dahlias, daylilies and sweet potatoes. These are simply swollen roots extending off a stem.
