There are a wide variety of begonias that you can grow. For the most part, these plants are not winter-hardy. They thrive in USDA zones 9 to 11, but you will need to grow them as an annual or indoors. Begonias are also grown as summer beds, while others are prized for the colors of their leaves and their blooms. As houseplants, begonias tend to grow anywhere from six to 12 inches (15.2 to 30.5 centimeters), but some varieties can reach up to at least five feet (152.4 centimeters) in height when grown outside. Most begonias like shaded areas to grow in, while some love to bask under the sun. Begonias thrive in well- or fast-draining soil because these plants do not like to be overwatered and can rot if left with too much moisture. Plant begonias when you're sure that there are no more threats of frost. These plants like balanced fertilizers, but if you're growing them for their leaves, use one with more nitrogen. Overall, you will need to protect begonias from mealybugs, powdery mildew, stem rot, and rhizome rot, among other diseases and pets.