Types of begonias: how to tell them apart and care for each

The begonias sold as houseplants fall into a handful of groups: rex and other rhizomatous begonias grown for their leaves, cane begonias such as angel wing and polka dot begonia, wax begonias, Rieger begonias and summer-flowering tuberous begonias. You can identify the group from the stem and roots in under a minute, and the group tells you most of what the plant needs.

How begonias are classified

Begonia is one of the largest genera of flowering plants. In 2021 the Royal Botanic Garden Edinburgh recorded the 2,000th accepted species, with 50 to 100 new species being added each year; older extension fact sheets still quote "1,000" or "1,500", which reflects how fast the count has grown. Species hybridize readily, and most begonias sold in US stores are hybrids, so gardeners classify them by growth habit rather than by species.

Different references slice the groups differently. The RHS uses four indoor groups: fibrous-rooted, cane-stemmed, rhizomatous and semi-tuberous (the winter-flowering B. × hiemalis hybrids). Iowa State Extension lists the types you will meet at a US garden center: wax, tuberous, Rieger, rex, cane, rhizomatous, trailing and shrub begonias. This article follows that practical list.

Identify your begonia in one minute

Colorado State Extension gives a handy check for canes: cane-like begonias have jointed stems, and at every joint you should find a leaf and/or a flower cluster.

Common identification mix-ups

• Rex vs. other rhizomatous begonias. Both creep on a rhizome. Rex leaves are metallic, multicolored and often spiral at the base; iron cross, eyelash and beefsteak begonias have plainer, tougher leaves. The tougher ones forgive drier air.
• Polka dot begonia vs. spotted angel wings. Both are canes. B. maculata has narrow olive leaves with even white dots and red undersides; many angel wing hybrids have broader leaves with irregular silver splashes. Care is the same.
• Rieger vs. tuberous. Both have big showy flowers. A Rieger is sold in bloom from fall into spring and stays green after flowering; a tuberous begonia flowers in summer and then yellows and dies back to a tuber, which is normal, not a sign that it died.

Rex begonias

Rex begonias (Rex Cultorum Group) are rhizomatous begonias grown entirely for foliage: asymmetric leaves in silver, burgundy, pink, purple and near-black, often with a spiral at the base. Flowers are small and best removed.

• Light: bright indirect; the RHS warns that direct sun scorches begonia leaves.
• Humidity: the most demanding group. Iowa State notes rex begonias prefer high relative humidity but dislike water on their leaves, so use a room humidifier, grouping or a pebble tray instead of misting. In a centrally heated US home in winter, a humidifier is usually the answer; see raising humidity.
• Water: when the top inch is dry; never let the rhizome sit wet.
• Temperature: the RHS gives 55°F as the winter minimum for rex; keep it away from cold glass and drafts.
• Rest: many rex begonias slow down or drop leaves in winter; cut water back and wait for spring growth.

Other rhizomatous begonias

Iron cross (Begonia masoniana), eyelash begonia (B. bowerae) and beefsteak begonia have the same creeping rhizome but tougher, less fussy leaves. Iowa State describes rhizomatous begonias as having swollen, root-like stems just beneath the soil surface. They suit shallow, wide pots because the rhizome spreads sideways, and the RHS recommends dividing them so that each piece of rhizome keeps one or more growing points. Care is like rex, but they cope better with ordinary room humidity.

Cane begonias: angel wing and polka dot

Cane begonias grow upright bamboo-like stems swollen at the nodes, with wing-shaped leaves and clusters of pink, red or white flowers that hang for weeks. Iowa State calls them often the easiest type to grow indoors because they adapt to varying light and moisture.

• Popular kinds: angel wing hybrids (often silver-spotted), 'Lucerna', 'Sinbad', and the polka dot begonia, Begonia maculata 'Wightii', with olive leaves, white spots and red undersides.
• Light: bright indirect with an hour or two of morning sun.
• Size: several feet indoors; Clemson HGIC notes cane-stemmed begonias may eventually reach 10 feet. Stake tall stems.
• Pruning: Clemson advises cutting back overly long stems in spring or early summer to encourage new growth at the base. Pinch tips too, or the plant becomes a few tall bare sticks.
• Humidity: average home humidity is usually fine.

Shrub begonias

Shrub-like begonias have many thin branching stems and often hairy or fuzzy leaves (for example Begonia 'Richmondensis'). They bloom on and off through the year and need regular pinching. Care is like cane begonias.

Wax begonias

Wax begonias (Semperflorens group) are the bedding begonias of US summer planters: low mounds of glossy green or bronze leaves and small pink, red or white flowers almost nonstop. Iowa State notes their durability outdoors, tolerating both part shade and full sun. Indoors they need the brightest window you have, including some direct sun.

Rieger (elatior) begonias

Rieger begonias, Begonia × hiemalis, are sold in full bloom as gift plants, with double or single flowers in many colors. The New York Botanical Garden describes them as complex hybrids of tuberous-rooted plants that do not fit neatly into the usual categories, and notes they are typically kept as a temporary decoration.

• NYBG recommends 60-65°F to extend flowering, never below 50°F, and away from drafts; Iowa State adds that Riegers prefer slightly cooler temperatures than other begonias.
• Light should be bright and filtered with no direct sun; an east window is ideal.
• After the flush they usually decline. Clemson suggests cutting elatior types back to within 3 inches of the crown; otherwise, enjoy them like a long-lasting bouquet.
• Overwatering and powdery mildew are the main killers; water at the soil, not over the leaves.

Tuberous begonias

Tuberous begonias (Begonia × tuberhybrida) produce the biggest flowers in the genus, rose- or camellia-like blooms in summer. They are best as shade plants for porches and patios rather than year-round houseplants.

• Season: Iowa State suggests planting tubers in containers in March and moving them outside in May in the Midwest.
• Dormancy: in fall the plant yellows; stop watering, cut off the shoots, lift the tuber and, as Clemson advises, store it in dry peat moss in a cool, dry place until spring.
• Light: bright shade; hot afternoon sun scorches leaves and shortens flowering.

Care comparison

Iowa State gives 60-80°F as the general comfort range for begonias, with regular, consistent moisture, and warns that roots rot quickly when soil stays wet for long. The RHS adds that most casualties it hears about were overwatered or kept in air that was too dry. More on placement in light for houseplants.

Which begonia should you choose?

• First begonia, average apartment: a cane begonia or polka dot begonia.
• Want color from leaves, can run a humidifier: rex begonia.
• Want flowers on a sunny windowsill: wax begonia; for a fall-winter display, a Rieger.
• Shady porch in summer: tuberous begonia.

Browse more options in flowering houseplants.

Toxicity

The ASPCA lists begonia as toxic to dogs, cats and horses. The toxic principle is soluble calcium oxalates; signs include vomiting and excessive salivation, and the tubers and roots are the most dangerous parts. Keep begonias out of reach and call your vet or ASPCA Animal Poison Control at (888) 426-4435 if a pet chews one; for a child, call Poison Control at 1-800-222-1222. See also toxic plants.

For general care of any type, see the begonia care guide.