foliage
DecorativeRex Begonia
Begonia rex-cultorum
Toxic to cats and dogs — keep it out of reach (source: ASPCA (Begonia, toxic)).
Some direct sun — an east or west window, or a few hours of direct light.
Keep evenly moist — water when the top inch of soil is dry.
Needs a little consistency, but nothing fancy.
Rex begonias are grown purely for their leaves — spirals and splashes of silver, purple, green, and red that few other houseplants match. They want bright indirect light and humidity, are toxic to pets, and sulk if their leaves stay wet.
About Rex Begonia
Rex begonias (Begonia rex-cultorum) are grown purely for their leaves, which spiral and splash silver, purple, green, and red in patterns few houseplants can match. They are hybrids bred from species native to Asia. They stay compact, suiting a small 2-litre pot, which makes them a lot of colour for very little space in a rental. They do want bright indirect light and humidity, and they are toxic to pets.
The care turns on water and air. Water the soil rather than the leaves, give the plant good airflow, and keep humidity up without letting the foliage stay damp. Bright indirect light brings out the leaf colour, while harsh direct sun scorches it. They are compact growers, around 0.2 to 0.3 metres tall and wide, and put their energy into leaves rather than the small flowers.
What it’s like to grow
Rex begonia is rated moderate, and most trouble comes down to moisture and airflow. Powdery mildew shows up in still, humid air, and rot follows when the crown or leaves stay wet, so water carefully and keep the air moving. Give bright indirect light for the best colour. It is toxic to cats and dogs, so site it where animals cannot chew on it.
What to expect
It asks for a little consistency, but nothing fancy. No sunny window? It also does fine under a clip-on grow light.
See what you’ll need to get started ↓Grow it alongside
Houseplants that want the same light, water and humidity are happy sharing a spot. See what thrives with Rex Begonia →
Tips
- Give bright indirect light to bring out the leaf colour.
- Water the soil, not the leaves, and give it good airflow.
- Raise humidity, but avoid leaving foliage damp.
Common problems
- Powdery mildew in still, humid air with poor airflow.
- Rot if the crown or leaves stay wet.
Common questions
Is Rex Begonia toxic to cats and dogs?
Rex Begonia is toxic to cats and dogs if eaten, so keep it out of reach of pets that chew. Source: ASPCA (Begonia, toxic).
How much light does Rex Begonia need?
Rex Begonia does best in medium, indirect light: near an east or west window, or a little back from a bright one. Direct midday sun can scorch it.
How often should I water Rex Begonia?
Water Rex Begonia when the top inch of soil feels dry, then let it drain. Aim for evenly moist, not soggy.
What temperature does Rex Begonia need?
Rex Begonia is happiest around 18–26 °C. It tolerates brief dips to about 10 °C, but cold drafts and sudden chills set it back.
Does Rex Begonia need high humidity?
Rex Begonia prefers humid air. Group it with other plants, stand it on a pebble tray, or run a humidifier — dry indoor air tends to brown the leaf tips.
Can I grow Rex Begonia without a sunny window?
Yes. Rex Begonia does well under an affordable clip-on grow light, so a bright window isn't essential.
How big does Rex Begonia get?
A compact foliage plant ~0.2–0.3 m tall and wide, grown for its patterned leaves.
How do I propagate Rex Begonia?
Propagate from leaf cuttings pinned onto moist soil.
What pests affect Rex Begonia?
Watch for mealybugs, thrips and fungus gnats. Check new growth and the undersides of leaves often, and treat early with a rinse or insecticidal soap before they spread.
Is Rex Begonia easy to grow?
Rex Begonia is moderately easy. It asks for some consistency with light and water, but nothing advanced.
Gear for Rex Begonia
Gear suggestions to get you started — general picks, not paid placements.
Pet-toxicity from the ASPCA. Care details are general guidance, not professional or veterinary advice. Photo: David J. Stang, CC BY-SA 4.0, via Wikimedia Commons (CC-BY-SA). Care info last updated 2026-06-08.