Begonia species - Rhizomatous Begonia
Medium to bright indirect
Let potting mix dry between waterings
18 inches (46 cm) tall, 2 feet (.61 m) wide
Delicate pink or white
Very hardy, but may develop stem and root rot, powdery mildew, and leaf spots
This is the largest group of begonias which produce thickened stems or rhizomes. They can creep along the surface, grow erect, or creep under the surface. These plants are admired for their unusual, and often colorful foliage, though many of these begonias also produce tall stalks of pink or white flowers. Popular Rhizomatous Begonias are Rex hybrids (Begonia x rex-cultorum) and Iron Cross Begonia (Begonia masoniana). They are a large group and need a variety of cultural environments. Too little light will give spindly growth, and too much light will give yellow foliage, and poor plant development.
These plants do well with average room temperatures during the day, 65-75 degree F (18-24 C) and slightly cooler temperatures, 55-65 degrees F (13-18 C) at night. They prefer a moderate humidity range between 40 to 70%, and all rhizomatous begonias like a well-drained soil; they will rot if it is wet and soggy. Feed with a good balanced fertilizer as long as the plants are actively growing, and avoid powdery mildew by keeping the leaves dry. All will root easily from a piece of rhizome or a leaf petiole.