Tender bulbs need to be dug up each fall and stored during the winter months to be planted again in the spring. However, prior to storing some tender bulbs, such as begonias, they need to be dried. The process of drying bulbs is often called curing. Begonia roots, while often referred to as bulbs, they are actually tubers.
Cut the foliage back to about 5 inches prior to digging up your begonias after the first killing frost. The foliage will turn yellow when this happens.
Dry the bulbs--with the 5-inch stems--indoors in an area that does not receive direct sunlight. Lay them out individually, such as on newspaper, for a quicker drying time.
Wait until the foliage and stems dry out, are loose and can be easily pulled off. This may take several days or even a week. Check on the bulbs every day to be sure they don't start to shrivel up.
Pull off the stems and foliage with your hands and remove as much soil as possible, but do not use water. They are now dried and ready to store in an open container of dry sand, vermiculite or peat moss in a cool and dark location, such as a garage or attic. Temperatures that are between 40 and 50 degrees F are ideal.