About this seed
About Madagascar periwinkle
Catharanthus roseus is an accepted species in the Apocynaceae family and is native to Madagascar. It is widely grown as a warm-season ornamental for its glossy leaves and long display of five-petalled flowers.
Sowing guide
- Use a fine, clean and free-draining seed mix.
- Sow shallowly, cover lightly and keep the tray dark until germination begins.
- Maintain approximately 22–25°C with even moisture and regular ventilation.
- Move emerged seedlings into bright light and avoid overwatering.
Kew's cultivation notes emphasize warmth and sensitivity to excess water. Natural variation still occurs between seed lots.
Growing on and safety
Pot seedlings individually after true leaves form, then increase sun gradually. Use a draining mix and water after the upper layer begins to dry.
Caution: all parts and sap should be treated as toxic. Keep plants and seeds away from children and pets, wear gloves if sap may contact skin, and do not use home-grown material as food or medicine.
Seed note: Seeds are living material. Germination speed and percentage vary with seed age, temperature, moisture and local growing conditions. Record the sowing date and treatment so later batches can be adjusted.