Begonias are considered bulbs, but they are actually tubers. According to the University of Minnesota, begonias are native to South America and Africa, and they come in a variety of colors like red, yellow, orange, white and pink. They produce flowers all season and can grow from 8 to 24 inches in height. Begonias grow well in the ground or in a container. Some varieties of begonia are hardy between USDA zones 6 and 10.
Choose a place in your garden for the tuberous begonias. They need well drained soil and shade in which to thrive. Add 4 to 5 inches of compost to the soil and work it in to a depth of 8 to 10 inches. Add 1 to 2 tbsp. of 10-10-10 fertilizer to the soil before you plant, and work it in to a depth of 4 to 5 inches.
Dig a hole as deep as the tuber and two times as wide. Press the begonia tuber into the soil until it is just below the soil line and fill the hole with soil. Make sure the pointed end is sticking up.
Water tuberous begonias well until the soil is moist but not soaking. Allow the soil to dry out slightly on top between each watering.
Add 1 to 2 tbsp. of 10-10-10 fertilizer once a month to the soil around the tuberous begonias. Water the soil well after you apply the fertilizer.
Dig up the tuberous begonias right before the first frost. Cut back the foliage, leaving only 1 to 2 inches. Dry the tubers in a dark room for one to three days and pack them in a box with vermiculite.