Bulbs are dormant when they have died back to nothing more than the brown, dried, fat root. That root has all of the nutrition that it will need for the next year’s successful bloom. It is important to keep bulbs cool and in dark, dry conditions until they are planted, whether they have been dug out of the ground after dying back or are fresh and new from the grower or supplier.
Some bulbs need to be chilled before planting in warm weather climates, like most of California and in the southern states. Tulips need chilling for about 6-8 weeks or longer if that is most convenient. I have planted tulips bulbs that have been left over and with almost 14 weeks of refrigeration and they have bloomed nicely. On one occasion, I planted some Darwin Hybrid tulips on April 1 after 22 weeks of chlling and they bloomed 2 weeks later with no roots!
Freesia, hyacinth, saffron crocus, and lilies need refrigeration if they are not planted after receiving them to keep them from beginning to keep the roots from beginning to grow. Daffodils do not need chilling but they do need to be kept in dark, dry storage as in a garage until time to plant. Other bulbs like giant scilla, lycoris, ranunculous, anamones and other warm weather bulbs and corms just need cool, dry, dark conditions.
The largest bulb in the world, I believe, is the Giant Scilla. It has lush large leaves in the fall which die back in the cold winter. In the spring it blooms on long stems which look like the fox tail lily and are five feet tall. There is a smaller version called the Delicate Scilla which grows to three feet. In my garden, the Delicate Scilla looks very similar to the taller one. The largest scilla has bulbs almost the size of a soccer ball and the smaller one the size of a grapefruit.
In the spring, the flower stems emerge and bloom with the florettes opening from the bottom up.
When in bloom, the bulbs look like naked ladies with part of the bulb visible and no foliage.
Planting the Giant Scilla and the Delicate Scilla: Prepare the soil with lots of loose material and add sand if the soil is heavy. I used an old compost pile and added coarse builders sand in order to maximize drainage as these desert adapted bulbs cannot sit in wet ground. Part of the bulb should be exposed after planting and these even rose up a little more as they developed roots as you can see in the first photograph. Its roots spread out over a good distance and so are not really useful in pots (plus they could be damaged by frost more easily).