After your Begonias finish blooming, it's important to allow the foliage to die back naturally. This process helps the plant store energy for the next growing season. As the leaves turn yellow and wither, reduce watering and allow the soil to dry out. Once the foliage has completely died back, you have two options:
If you live in a region with mild winters, you can leave the bulbs in the ground. Apply a layer of mulch to protect the bulbs from any unexpected temperature fluctuations.
In colder climates, it's best to dig up the bulbs for storage. Carefully lift the bulbs from the soil, remove excess dirt, and allow them to air-dry for about a week. Once dry, store them in a well-ventilated, cool, and dark place, such as a garage or basement. Use a container filled with peat moss, sawdust, or vermiculite to store the bulbs, ensuring they don't touch each other to prevent rot.