Vinca is the genus and common name for two species of vining plants cultivated as ornamental ground covers for their glossy leaves and purple, pinwheel-like flowers. Once established, vinca tolerates drought and moderately cold temperatures with minimal damage to its health or appearance. However, the seedlings cannot tolerate dampness or chilly temperatures, so it is best to germinate the seeds when the night temperature is 25 to 30 degree Celsius
Fill a 2-inch-deep nursery flat with fresh, sterile seedling compost. Leave a 1/4-inch gap between the compost and the top of the flat. Firm the compost with the palm of your hand to create a smooth, even surface.
Lay out the vinca seeds across the surface of the compost. Space the seeds 2 inches apart. Press them halfway into the compost. Cover the seeds with a 1/4-inch-thick layer of compost.
Mist the compost with a spray bottle to settle it. Spray the compost until it feels wet at a depth of 1 inch. Maintain a moderate level of moisture in the top inch of compost while the vinca seeds germinate.
Cover the nursery flat with a black plastic trash bag to create the dark, warm conditions vinca seeds require to germinate. Remove the trash bag during germination only to water the seeds. Replace the bag immediately after watering.
Watch for germination within two weeks after sowing the vinca seeds. Decrease watering and remove the black bag after the seeds germinate. Allow the compost to dry out in the top 1/2 inch before adding more water.
Remove the weakest, least vigorous vinca seedlings from the flat. Transplant the remaining seedlings into individual 2-inch starter pots filled with potting soil once they develop three or four sets of healthy, mature leaves.
Move the vinca seedlings to a warm, bright location where they will receive six hours of bright, diffuse sunlight each day and temperatures above 25 C. Transplant them into the garden once outdoor temperatures reliably top 25 C during the day. Space the plants two feet apart.
Different Varieties of Vinca's available at Biocarve Seeds: