Periwinkle (Catharanthus roseus)
Apocynaceae

Varieties
White flowered, Purple flowered and Nirmal (white flowered variety: from CIMAP) are the three types of periwinkle. ‘Nirmal’ and ‘Dhawal’ are the released cultivars of white flowered type.

Soil and climate
It is suited to all types of soil and tropical climatic conditions. Well distributed annual rainfall of 100 cm or more is ideal for cultivation. It is also suitable for raising as a rainfed crop.

Seeds and planting
It is propagated through seeds either by direct sowing or through transplanting.

Seed rate
About 2.5 kg/ha is required for direct sowing and 0.5 kg/ha for seedling transplantation. 45 - 60 days old seedlings are transplanted at a spacing of 45 x 20 cm during June - July or September - October.

Manuring
Apply FYM at 20 t/ha and N, P and K at 25:50:75 kg/ha as basal dose. On 60 days after transplanting apply 50 kg N as top dressing.

Aftercultivation
The crop requires 2 weedings, the first at 90 days after sowing/transplanting and second 60 days after the first weeding.

Harvest
The crop becomes ready for harvest of roots after one year. Two leaf strippings can be taken, the first one after 6 months and the second after 9 months of sowing.  Aerial parts are cut and the soil is ploughed for harvest of roots.  Fruits are collected without damage.

Yield    

Source
1.http://upload.wikimedia.org/wikipedia/commons/thumb/5/55/Madagascar_periwinkle.jpg/800px-Madagascar_periwinkle.jpg