What type of begonia would do well in full sun? Do they need fertilzer for blooms? ZONE 8B.
Begonia
Wax begonias can take some sun, even full sun if grown in cool summer areas. I don't know if they could take full sun in our zone. Try a few of the hardier types. I found a list of a few with descriptions. Use a balanced fertilizer.
http://www.yardener.com/WaxBegoniaChoices.html
Scarletta is a dark leaved, red blooming begonia that can take full sun. They make the typical mounded plant and bloom almost year round here in Houston for me. The only thing they don't like is wet feet. If not in well draining area, they get rot very easily. As long as they are in a well drained site and not overwatered, they'll be fine without much care. I've found the ones with lighter leaves and blooms are more sun sensitive.