Known as the painted-leaf begonia B. rex is originally from Assam and. with its closely-related hybrids in the Rex Cultorum Group, has the most dramatic foliage of any of the begonias. They are rhizomatous with red. hairy stems bearing large, puckered leaves that can be hairy both on top and underneath. The leaves are rich, metallic green, splashed with silvery white above and dull red beneath). The winter-borne flowers are pink.
The Rex Cultorum Group of hybrids is large, with most plants being grown for their foliage rather than their flowers. The leaves are heart- shaped, up to 2 ft. (50 cm) in length, and have striking patterns in a range of colors, including wine-red, and shades of green, bronze, and silver.
Size: Height 1 ft. (50 cm), spread to 5 ft. (90 cm).
Light: Indirect sunlight.
Temperature: Normal room.
Moisture: Keep the soil mix moist, but not wet.
Feeding: Use standard liquid fertilizer every two weeks in spring and summer.
Propagation: Gut 2—5 in. (5—7 cm) sections of rhizome, each with a growing point, plant shallowly, and cover with a plastic bag. Alternatively, cut a healthy leaf with 1—2 in. (2—5 cm) of leafstalk, plant it at an angle of 45° in a pot or tray of soil, and enclose it all in a plastic bag. Pot up when the small new plantlets have 2—5 leaves.
Special needs: Direct sunlight may scorch the leaves. Overwatering can cause rotting.