The Story
Plant Bio
Catharanthus roseus, Madagascar periwinkle, is a compact bushy tender perennial from Madagascar, six to eighteen inches high, grown as a summer annual. Glossy dark green oblong leaves cover branching stems, and flat five-petalled tubular flowers one to three inches across open in white, pink, magenta and red, often with a contrasting eye, from summer to frost.
It is the source of the alkaloids vincristine and vinblastine, which transformed the treatment of childhood leukaemia — and the same compounds make every part of the plant toxic if eaten. It thrives on heat, drought and poor soil, and the commonest way to kill it is kindness: overwatering causes root rot within days.
Uses & Benefits:
Essentials
At a Glance
Plant Type
Annual
Height
12 inches
Width
10 inches
Light
Full Sun, Partial Sun
Zones
7, 8, 9, 10
Water
Low
Humidity
Moderate
Lifespan
Perennial
Native To
Madagascar
Toxicity
All parts toxic if eaten
Planting
How to Grow
- Plant out only once soil and nights are genuinely warm.
- Give it full sun and sharply drained soil.
- Water sparingly; let the surface dry between times.
- Avoid rich feeding, which reduces flowering.
- Do not deadhead; it sheds spent flowers cleanly.
- Keep it away from pets and small children.
Pro Tip
Overwatering kills far more of these than drought — plant it into warm dry soil and then largely leave it alone.
Keep It Thriving
Care Guide
Do
- Plant into warm, well-drained soil ☀️
- Water sparingly once established 💧
- Let it self-clean rather than deadheading 🌸
- Keep it out of reach of pets 🐈
Don't
- Plant out into cold soil ❌
- Overwater it ❌
- Let anyone eat any part of it ❌
Seasonal Care Calendar
| Task | Jan | Feb | Mar | Apr | May | Jun | Jul | Aug | Sep | Oct | Nov | Dec |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Plant Out | ||||||||||||
| Water |
Watch Out For
Pests & Diseases
Common Pests
Common Diseases
In the Garden
Landscape Uses & Companions
Landscape Uses
Multiply
Propagation Methods
Good to Know
Common Questions
Madagascar Periwinkle questions
What zones can Madagascar Periwinkle grow in?
Madagascar Periwinkle is hardy in USDA Zones 7–10. Inside that range it survives winter in the ground; outside it, grow it as an annual or a container plant you protect.
Is Madagascar Periwinkle deer resistant?
Yes — Madagascar Periwinkle is rated deer-resistant. Deer typically pass it over, though extreme hunger can override any plant's defenses.
When does Madagascar Periwinkle bloom?
Madagascar Periwinkle typically blooms in summer to frost through late summer. Exact timing shifts a week or two with your zone — Sow's bloom calendar maps it to your garden.
Does Madagascar Periwinkle need full sun?
Madagascar Periwinkle does best in full sun to part shade. In hot climates, afternoon shade keeps blooms fresher longer.
Is Madagascar Periwinkle drought tolerant?
Yes — once established (usually after the first full season), Madagascar Periwinkle handles dry spells with minimal watering. Water deeply its first year to build the root system that makes that possible.
More Catharanthus to compare
Keep exploring
Explore the genus
Hardy in your zone?
Grow Madagascar Periwinkle with confidence
See it in a design of your actual yard, get zone-matched care reminders, and track it season by season in your garden journal.