A bulb is an underground storage organ that contains the elements necessary for the development of a plant. It is made up of a bud protected by scaled leaves, which contain the plant's nutritional reserves.
Flower bulbs are therefore perennial plants, which can grow back from year to year. Do not let yourself be fooled by the term “flower bulbs” which can include bulbs, corms or plants with tuberous roots. Only a few spring flowers are considered true bulbs, such as the tulip, amaryllis, narcissus, hyacinth or bulbous iris. In summer, among the real flower bulbs we find freesias, lilies or even oxalis. In the vegetable garden, the most common bulbs are garlic and onion, and of course their cousin, the shallot. The bulbs are propagated by division, taking the largest bulbils that appear each year around the main bulb. This gives them an invasive, even tracing appearance.