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Madagascar periwinkle

Catharanthus roseus, Apocynaceae

Sources last read 14 September 2026.

Middling It gives warning, with time to act.

Also called Annual Vinca, Cape periwinkle, cayenne jasmine, East Indian periwinkle, old maid, Periwinkle, Rose Periwinkle, rosy-flowered Indian periwinkle and Running Myrtle.

Madagascar periwinkle (Catharanthus roseus), the whole plant.
Vinayaraj, CC BY-SA 4.0 · Wikimedia Commons

Madagascar periwinkle is toxic

  • Toxic to cats. Toxic principle: Vinca Alkaloids. Clinical signs: Vomiting, diarrhea, low blood pressure, depression, tremors, seizures, coma, death. ASPCA
  • Toxic to dogs. Toxic principle: Vinca Alkaloids. Clinical signs: Vomiting, diarrhea, low blood pressure, depression, tremors, seizures, coma, death. ASPCA
  • 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

Sources file this plant under other names: Vinca rosea (ASPCA). Citations below point at the name its source uses.

Light
Full sun
RHS · read 13 September 2026
Water
Moist but well-drained or Well-drained
RHS · 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
Chalk, Loam, Sand; pH Acid or Alkaline or Neutral
RHS · read 13 September 2026
Toxic to cats
Toxic
ASPCA, filed as Vinca rosea · read 13 September 2026
Toxic to dogs
Toxic
ASPCA, filed as Vinca rosea · read 13 September 2026
Harmful to people
No statement of harm to people is published for this plant; that absence is not evidence it is safe.
RHS · read 13 September 2026

How it usually goes wrong

Brown, papery patches on the leaves nearest the glass

The damage on the Madagascar periwinkle faces one way. Turn the pot round and the other side is clean.

Even a plant described as full sun can take more through glass than it would outdoors, because glass removes the breeze that carried the heat away.

Telling it apart: The edge of the damage. Scorch has a sharp boundary; rot and infection have a soft, spreading one.

RHSMadagascar periwinkle brown leaf tips and edges: causes
Buds form and fall before they open

Buds on the Madagascar periwinkle stop swelling, turn pale at the base and fall, usually a few at a time over a week or two.

Sudden changes in light, warmth or watering cause buds to be abandoned, because a bud is expensive and the plant cannot tell whether conditions will recover. Its source describes full sun.

Telling it apart: When the buds dropped. Within days of a move or a dry spell is the change; buds that drop with nothing changed point at uneven watering or pests on the buds.

RHSMadagascar periwinkle leaves falling off: causes
Dry, curled edges on leaves near a heater

Leaves on the side of the Madagascar periwinkle nearest a heater or vent brown at the edges while those on the far side stay clean.

Dry air takes water from the leaf surface continuously, and the tissue at the edge is last in the queue for what the roots send up. Penn State Extension notes there is no single humidity figure that suits every indoor plant.

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 ExtensionMadagascar periwinkle brown leaf tips and edges: causes
Yellow, limp leaves at the base

The Madagascar periwinkle yellows from the base up. Affected leaves bend rather than snap, and the pot is still heavy several days after watering.

Soil described as moist but well-drained or well-drained is a drainage instruction as much as a watering one. Compost that stays saturated suffocates the fine roots that do the drinking.

Telling it apart: The soil, not the leaf. Wet compost under yellowing leaves points one way and dry compost the other, and the leaves alone will not tell you which.

RHSMadagascar periwinkle leaves turning yellow: causes

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

Routine care

Watering
During growth, water moderately and feed monthly with a balanced liquid fertiliser. Give little water in winter.
RHS · read 13 September 2026
Feeding
While growing, water moderately and feed monthly with a balanced liquid fertiliser.
RHS · read 13 September 2026
Propagation
Seed
NC State Extension · read 13 September 2026
In early spring sow seed at 13 to 18°C. Other options: in late spring, softwood cuttings; in summer, semi-hardwood cuttings.
RHS · read 13 September 2026
Pruning
Pruning is not needed.
RHS · read 13 September 2026
Pests and diseases
Diseases: southern bacterial wilt, Phytophthora blight and root rot, black root rot.
NC State Extension · read 13 September 2026
Can be troubled by glasshouse red spider mite and glasshouse whitefly. Diseases: usually none.
RHS · read 13 September 2026

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About the plant

Catharanthus roseus, commonly known as bright eyes, Cape periwinkle, graveyard plant, Madagascar periwinkle, old maid, pink periwinkle, rose periwinkle, is a perennial species of flowering plant in the family Apocynaceae. It is native and endemic to Madagascar, but is grown elsewhere as an ornamental and medicinal plant, and now has a pantropical distribution. It is a source of the drugs vincristine and vinblastine, used to treat cancer. It was formerly included in the genus Vinca as Vinca rosea.

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

Native range
E. & S. Madagascar
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Madagascar
NC State Extension · read 13 September 2026
Madagascar
RHS · read 13 September 2026
Climate
seasonally dry tropical
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Growth form
subshrub or shrub
World Checklist of Vascular Plants, June 2026 release, CC BY.
Kew WCVP · read 13 September 2026
Annual, Ground Cover, Perennial; habit erect, spreading
NC State Extension · read 13 September 2026
Bushy (evergreen)
RHS · read 13 September 2026
Size
Height 6–18 in; width 8–12 in
NC State Extension · read 13 September 2026
Height 0.1-0.5 metres; spread 0.1-0.5 metres after 2–5 years
RHS · read 13 September 2026
Flowering
Flowers gold/yellow, pink, purple/lavender, white; blooms in fall, summer
NC State Extension · read 13 September 2026
Flowers pink in spring and summer; red in spring and summer; white in spring and summer
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.

Compounds found in this plant brought a major advance in treating some types of leukemia.
NC State Extension · read 13 September 2026

Common problems with Madagascar periwinkle

More of the Apocynaceae family

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.