Plants with a subterranean bulb that holds reserves for the following year during the growing season are often all grouped under the term bulbs.
However, there are actually several different types of bulbs:
- true bulb: a collection of fleshy leaves covering the almost complete embryo of the future plant.
- tuber: an underground swelling of the root or stem.
- corm: a thickening of the base of the stem.
- rhizome: a subterranean stem with roots and aerial shoots.
Tulips and daffodils belong to the large category of hardy bulbs, i.e. bulbs that are planted in the fall and weather well under snow throughout the winter. Gladiolus, cannas, dahlias and begonias, on the other hand, must be sheltered from freezing weather if they are to blossom the following year.
They are thus called non-hardy or tender bulbs.
The following are some suggestions for growing some of the more popular non-hardy bulbs.