Rex begonia (Begonia rex-cultorum) is a semi-tropical perennial plant normally grown as an outdoor container plant or houseplant. The forms sold commercially are carefully cultivated varieties of the B. rex species native to parts of eastern Asia. If planted in the garden (a relatively rare occurrence), rex begonia is grown as an annual in all but the warmest climates.
Among the various types of begonias, Begonia rex is one of the most beautiful and stunning plants. Sometimes called painted-leaf begonias or fancy-leaf begonias, these plants are known for their showy, sometimes jaw-dropping leaf coloration. They frequently have large leaves (up to 6 inches long) that are brightly colored in various shades of green, red, silver, and even purple. These plants are grown almost exclusively for their foliage—their blooms tend to be small and less showy, so many growers pinch off blooms to maintain breathtaking leaf displays. Some types of rex begonias go into dormancy during the winter.