How to Grow and Care for Rex Begonias
Rex begonia, also commonly known as painted-leaf begonia or fancy-leaf begonia, is known for its large variegated leaves in brightly colored shades of green, red, silver, and even purple. Rex begonia grows at a moderate pace, reaching maturity of 8 to 12 inches within a few years.
This semi-tropical perennial plant does best with bright, indirect light and does not tolerate full sunlight. It likes moisture but should dry out partially between waterings. Rex begonia is an extremely easy houseplant to care for, however, take care if you have animals as this plant is toxic to both people and pets.
| Common Name | Rex begonia |
| Botanical Name | Begonia rex-cultorum |
| Family | Begoniaceae |
| Plant Type | Herbaceous, perennial |
| Mature Size | 12-18 in. tall, similar spread |
| Sun Exposure | Partial, shade |
| Soil Type | Well drained |
| Soil pH | Acidic |
| Hardiness Zones | 10-12 (USDA) |
| Native Area | Asia |
| Toxicity | Toxic to people, pets |
Rex Begonia Care
Here are the main care requirements for growing rex begonia:
- Provide rex begonias with plenty of bright, indirect sun, but keep them out of direct sunlight.
- Keep the plant moist, but avoid overwatering; allow the soil to dry partially between waterings.
- Place the plant in an area with temperatures between 60°F and 70°F.
- Use a porous potting mix in a relatively shallow pot.
- Feed the plant regularly.
- As a houseplant, rotate frequently to expose it to equal light on all sides.


Light
Rex begonias like bright, indirect light year-round. Because they are not aggressive bloomers, they can tolerate less light than other begonias and will thrive under fluorescent lights.
Soil
Airy, light, fast-draining soil is best for growing rex begonias in containers. Their fine root systems prefer a well aerated peat-based potting soil.
Water
Rex begonias require regular water, but don't overwater them. The soil should feel slightly, yet evenly moist. Allow the soil surface to become dry to the touch before watering.
Don't let the soil become overly dry or the plant will begin to wither. The plants thrive on humidity but don’t let the leaves get wet, or you risk powdery mildew.
Temperature and Humidity
Rex begonias do best in moderate temperatures (60°F to 70°F) and moderately high humidity (around 50 percent). Growth will slow in freezing temperatures and some types of begonias go into a dormant period during the winter due to lack of light.
As with other begonias, rex and other begonias grown at home prefer the same humid, gentle environment in which understory ferns thrive.
Fertilizer
Use liquid fertilizer at half strength every two weeks during growing season.
From: thespruce