Why Plants Die
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Bougainvillea

Bougainvillea glabra, Nyctaginaceae

Sources last read 14 September 2026.

Middling It gives warning, with time to act.

Also called Lesser Bougainvillea, Paper Flower and Paperflower.

Bougainvillea (Bougainvillea glabra), the whole plant.
পাপৰি বৰা, CC BY-SA 4.0 · Wikimedia Commons

Toxicity is partly unassessed

  • Not assessed for cats. This plant is not on the ASPCA list. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.
  • Not assessed for dogs. This plant is not on the ASPCA list. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.
  • Not assessed for people. RHS publishes no harm statement for this plant. That is not a finding of safety: none of the sources read for this site gives an answer either way. Treat it as unknown.

What the sources say about its care

Light
Full sun
RHS · read 11 September 2026
Water
Moist but well-drained
RHS · read 11 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 11 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 11 September 2026
Soil
Loam; pH Acid or Alkaline or Neutral
RHS · read 11 September 2026
Toxic to cats
Not on the ASPCA list. That is not a finding of safety.
ASPCA · read 11 September 2026
Toxic to dogs
Not on the ASPCA list. That is not a finding of safety.
ASPCA · read 11 September 2026
Harmful to people
No harm statement is published for this plant; that absence is not evidence it is safe.
RHS · read 11 September 2026

How it usually goes wrong

Crisp margins that appear in winter

The bougainvillea shows browning on many leaf blades at once, all at the margin, with no spots or soft patches anywhere.

Leaf margins are the end of the water supply, so they are the first tissue to run short when the air takes more than the roots can send. Penn State Extension cites 30% to 60% as the recommended indoor range, and a heated room in winter sits below it.

Telling it apart: Where the plant stands. Browning concentrated on the side facing a heater points at the air.

Penn State ExtensionBougainvillea brown leaf tips and edges: causes
Lower leaf blades collapse and yellow within days of a watering

A sour smell from the compost is common on a bougainvillea, and the leaves nearest the soil come away when pulled. The surface may look dry while everything beneath it is not.

The source for this plant describes moist but well-drained soil. Compost that stays saturated loses the air spaces fine roots grow into, and those roots die back first.

Telling it apart: Weigh the pot in your hand. A pot still heavy a week after watering is holding more water than the roots are using.

RHSBougainvillea leaves turning yellow: causes
Pale dry areas across the upper leaf blades only

Affected tissue goes pale and then papery, and the boundary follows where the light falls rather than the shape of the leaf blade.

Full sun is what its source names, and outdoors that sun comes with moving air that cools the foliage. Behind still glass the same light heats the tissue well above the room, and the exposed patches dry out first.

Telling it apart: Which side. Damage confined to the lit side is light; damage spread evenly is not.

RHSBougainvillea leaves turning yellow: causes

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

Routine care

Watering
Lesser Bougainvillea suits a hot, dry climate; water it thoroughly but let it dry out between waterings.
NC State Extension · read 13 September 2026
From spring, as plants resume active growth, water more and use a balanced liquid feed until colour shows in the bracts, then change to a high potassium feed. In autumn, water less and stop feeding.
RHS · read 13 September 2026
Feeding
From spring, as active growth resumes, water more and give a balanced liquid feed until colour shows in the bracts, then change to a high-potassium feed. In autumn, water less and stop feeding.
RHS · read 13 September 2026
Propagation
Seed, stem cuttings
NC State Extension · read 13 September 2026
Layer in early spring; in summer take semi-ripe cuttings; in winter root hardwood cuttings over bottom heat.
RHS · read 13 September 2026
Pruning
Prune right after flowering to keep the shape you want.
NC State Extension · read 13 September 2026
Follow pruning group 12.
RHS · read 13 September 2026
Pests and diseases
Can be troubled by glasshouse whitefly, aphids, mealybugs and glasshouse red spider mite. Diseases: usually none.
RHS · read 13 September 2026

Move something and watch

Loading the simulator. It needs JavaScript; the care table above does not.

About the plant

Bougainvillea glabra, the lesser bougainvillea or paperflower, is the most common species of bougainvillea used for bonsai. The epithet 'glabra' comes from Latin and means "bald".

From Wikipedia, CC BY-SA 4.0 · read 13 September 2026

Native range
E. & S. Brazil
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
native to Brazil and Peru
NC State Extension · read 13 September 2026
Brazil
RHS · read 13 September 2026
Climate
wet tropical
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Growth form
climbing shrub or liana
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Annual, Perennial, Shrub, Vine; habit arching, cascading, climbing, multi-trunked, spreading
NC State Extension · read 13 September 2026
Climbing (semi evergreen)
RHS · read 13 September 2026
Size
Height 120–240 in; width 72–120 in
NC State Extension · read 13 September 2026
Height 4-8 metres; spread 2.5-4 metres after 5–10 years
RHS · read 13 September 2026
Flowering
Flowers cream/tan, gold/yellow, white; blooms in spring, summer
NC State Extension · read 13 September 2026
Flowers pink in summer and autumn
RHS · read 13 September 2026
Uses

What sources record people using this plant for. A traditional or medicinal use listed here is a record of use, not advice to eat it or treat anything with it.

It serves as a plant-based insecticide. Mexicans take an infusion of it for stomach, gut and respiratory problems.
NC State Extension · read 13 September 2026

Common problems with Bougainvillea

Plants with similar care

Sources

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.