Wax begonia

What the sources say about its care

Sources file this plant under other names: Begonia semperflorens Cultorum Group (RHS). Citations below point at the name its source uses.

Light

Full shade, Partial shade

RHS, filed as Begonia semperflorens Cultorum Group · read 13 September 2026

Water

Moist but well-drained or Well-drained

RHS, filed as Begonia semperflorens Cultorum Group · read 13 September 2026

Humidity

No source read publishes a humidity figure for any plant on this site. What follows is general guidance for foliage plants.

ASHRAE recommends indoor relative humidity between 30% and 60% 30–60%

Penn State Extension · read 13 September 2026

Temperature

How cold this tolerates, not what it prefers. No source read for this site publishes a preferred range for a plant indoors.

H1C — 5–10°C 5–10 °C

RHS · read 13 September 2026

Soil

Clay, Loam, Sand; pH Acid or Neutral

RHS · read 13 September 2026

Toxic to cats

Toxic

ASPCA names a variety or cultivar (Begonia semperflorens cultivar) of this species.

ASPCA, filed as Begonia semperflorens cultivar · read 13 September 2026

Toxic to dogs

Toxic

ASPCA names a variety or cultivar (Begonia semperflorens cultivar) of this species.

ASPCA, filed as Begonia semperflorens cultivar · read 13 September 2026

Harmful to people

No harm is recorded, only a note: the bulbs are ornamental and should not be eaten. Use gloves and protective gear when handling it.

RHS · read 13 September 2026

How it usually goes wrong

Leaf tips go crisp and brown

A narrow dry border on the wax begonia, often with a faint yellow line against the healthy tissue. It appears on several leaves at once rather than spreading from one.

Transpiration rises as the air dries, and the tissue furthest from a vein loses first. Penn State Extension notes there is no single humidity figure that suits every indoor plant, which is why this site publishes a range rather than a number.

Telling it apart: Look at the pot rim and the soil surface. A white crust points at a build-up from tap water or feed rather than at the air. Penn State also reports misting and pebble trays do little to the humidity around a plant.

Penn State ExtensionWax begonia brown leaf tips and edges: causes

Leaves but no flowers

The wax begonia flowered well at first, then less each season, while its leaves stayed healthy and new stems grew longer.

Its RHS shade rating describes a garden, where even full shade under open sky is brighter than most rooms. Flowers cost more than leaves, so a plant kept back from the window keeps growing leaves while it builds few buds or none.

Telling it apart: The spacing of the newest leaves. Stretched growth means the light is short; normal spacing points at timing or feeding.

RHSDiagnose no flowers or dropped buds on this Wax begonia

Long bare stretches of stem between leaves

The newest leaves on the wax begonia are the palest and smallest, and the stems carrying them bend toward the brightest side of the room.

RHS rates it for full or partial shade, but those are garden terms: shade under open sky is brighter than most rooms away from a window. A spot that looks bright to the eye can still be short of that, and the plant stretches toward the glass.

Telling it apart: Spacing. A plant short of light stretches; one short of nitrogen keeps its spacing and only loses colour.

RHSDiagnose leggy growth on this Wax begonia

The lowest leaves on each stem turn yellow and hang

Whole leaves yellow at once rather than browning at a margin, and the wax begonia looks deflated despite soil that has not dried since it was watered.

Kept wetter than the moist but well-drained or well-drained its source describes, the root tips die back. A plant with fewer working roots cannot drink, which looks from above exactly like one that has not been watered.

Telling it apart: The smell. Healthy compost smells of earth; compost that has been wet too long does not.

RHSDiagnose yellowing leaves on this Wax begonia

Not sure which it is? Ask the diagnosis questions for Wax begonia.

Routine care

Propagation

Increase from seed or from stem, tip or leaf cuttings.

RHS · read 13 September 2026

Pruning

Pruning is not needed.

RHS · read 13 September 2026

Pests and diseases

Can be troubled by aphids, vine weevil, glasshouse thrips, mites, mealybugs and caterpillars. Diseases: rhizome rot, stem rot, powdery mildews and grey moulds.

RHS · read 13 September 2026

About the plant

Native range

S. Brazil to NE. Argentina

World Checklist of Vascular Plants, June 2026 release, CC BY.

Kew WCVP, filed as Begonia cucullata var. hookeri · read 13 September 2026

Climate

seasonally dry tropical

World Checklist of Vascular Plants, June 2026 release, CC BY.

Kew WCVP, filed as Begonia cucullata var. hookeri · read 13 September 2026

Growth form

subshrub

World Checklist of Vascular Plants, June 2026 release, CC BY.

Kew WCVP, filed as Begonia cucullata var. hookeri · read 13 September 2026

Bushy (deciduous)

RHS · read 13 September 2026

Size

Height 0.1-0.5 metres; spread 0.1-0.5 metres after 1–2 years

RHS · read 13 September 2026

Flowering

Flowers pink in summer and autumn; red in summer and autumn; white in summer and autumn

RHS · read 13 September 2026

Common problems with Wax begonia

• Brown tips and edges

Other Begonia

• Polka dot begoniaBrown brittle margins with a green centre
• Rex begoniaBrown brittle margins with a green centre
• No photograph yetBegonia taliensisSourced care, difficulty not yet judged
• Begonia venosaSourced care, difficulty not yet judged
• Elephant-Ear BegoniaSourced care, difficulty not yet judged
• Iron Cross BegoniaSourced care, difficulty not yet judged

More of the Begoniaceae family

• No photograph yetMaple Leaf BegoniaSourced care, difficulty not yet judged
• Metallic Leaf BegoniaSourced care, difficulty not yet judged

Plants with similar care

• Blue passion flowerA thin dry rim that crumbles between the fingers
• Bush lilyDry, curled edges on leaves near a heater
• Dog roseEdges of the leaves brown while the middle stays sound
• English lavenderBuds form and fall before they open
• Flaming KatyA thin dry rim that crumbles between the fingers
• Hardy fuchsiaBrown, papery patches on the leaves nearest the glass

Sources

• ASPCA · read 13 September 2026
• Kew WCVP · read 13 September 2026
• Penn State Extension · read 13 September 2026
• RHS · read 13 September 2026

What this does not cover

The figures above are what published sources say, not measurements of the plant in your room. They say nothing about your pot size, your water, the season, or how far from the glass the plant stands, and those decide more than any figure here does.

Humidity has no species figure because no source read for this site publishes one, and the only temperature published for this plant is a cold floor. The simulator fills those gaps with general figures for its kind of plant, marked as general and listed on how we read sources. Where a toxicity row says the plant was not assessed, that is the absence of a finding and not a finding of safety.

If something is already wrong, the diagnosis tool asks about the soil, the window and the watering, which is where the answer usually is.