Although they are known for being one of the more popular American houseplants, begonias are also frequently used in flowerbeds or hanging pots. The popularity of begonias is due to their general pleasantness. They are easy to grow in fertile, adequately drained soil, and their flowers and foliage are very attractive, especially when planted in large groups.
Depending on the species, begonias tend to grow anywhere between 8 inches (20 centimeters) and 2 feet (61 centimeters) tall, with flowers white, yellow, orange, red or pink in color. The most widely grown species of begonia is the wax begonia, which is known for its hardiness and durability. The wax begonia can survive the cooler temperatures of the early spring and continue to bloom through the pulsing heat of a southern summer. Similarly, although wax begonias may fare better with a little bit of shade, they can still grow well out in the open sun. Wax begonias have heart-shaped leaves -- often with a red or mahogany tint -- and flowers of white, pink or red. For ideal results, wait until after the last frost of the winter to transplant any begonias that may have been inside for the winter, and be sure to arrange the plants 6 to 8 inches (15 to 20 centimeters) apart [source: Clemson Extension Home & Garden Information Center].
While wax begonias may thrive in the summer heat, tuberous begonias do not. They will wilt in the peak of summer. Many gardeners plant tuberous begonias in early March and then again in September to add color to the building and waning weeks of summer. Tuberous begonias also need much more shade than wax begonias, especially when germinating, and require more watering and fertilization. Tuberous begonias grow to be between 12 to 18 inches (30 to 45 centimeters) tall, with flowers 2 to 4 inches (5 to 10 centimeters) wide. They're white, yellow, orange, red and pink in color [source: Kessler].
In addition to wax begonias and tuberous begonias, there are several other species of begonias, including many low-maintenance hybrids and hardy begonia, a leafy perennial.