General How to store Bulbs
If it is absolutely necessary to store them for a short time before planting them, open the cartons and any plastic that is around the roots. If the roots appear dry, soak them for a few hours in warm water. Thereafter store in slightly moist peat moss in a cold, but not freezing location until you can plant.
You will receive your bulbs just before the ideal planting time. If your shipment contains bulbs that dry out fast and you want to store them, keep them in a pot or bag full of peat-dust or sand until you plant them. It is however, possible to store them in a dark, cool and dry place that is well ventilated. Make sure that the temperature is constant. Do not delay planting the bulbs any longer than is necessary. Remember your bulbs long for some cool, moist earth and they should be planted at least two weeks before it starts to freeze. Bulbs are not seeds and will not keep until next year.
Keep Them Cool
Ideally, bulbs should be kept in a sleepy state until planting day. This is best achieved by regulating their temperature. A few types are a bit more finicky, but as a general rule most bulbs can be safely stored for up to several weeks in a cool, dry place where temperatures hover between 38 - 45 degrees F. Your refrigerator (see Avoid Ethylene below), is the ideal spot. In the short term, bulbs will also stay inactive at slightly higher temperatures (between 55-65 degrees F), but they are at a greater risk for drying out. Until bulbs are rooted in the soil, freezing temperatures will harm the embryos. As long as temperatures don't fall below 32 degrees F, unheated basements, garages, closets, or utility rooms will work just fine, too.
Let Them Breathe
Even in a state of suspended animation, your bulbs will continue to produce a small amount of moisture. For this reason, it's important to store your bulbs in a way that allows them to breathe, while at the same time prevents them from drying out. Open trays or paper bags work best. Avoid plastic, which can collect moisture and produce mold.
Bulbs and Ethylene
If you decide to refrigerate your bulbs before planting them, make sure you keep them away from apples and other fruit. Many types of fruit release ethylene gas, which assists in the ripening process. In an enclosed space like a refrigerator, this gas can build up and cause damage to the flower buds.
When To Skip Storage
If it's going to be longer than a week from the time you buy your bulbs until you're ready to plant, you need to think about proper storage. If it's only going to be a few days, don't worry about it. Most bulbs will be fine just lying around the house in the bag or box they came in. Just make sure you keep them away from heat sources like radiators, air ducts, and direct sunlight, which can dry them out in only a matter of hours.