Vinca Flower How Long Does It Last. Raise the lights as the plants grow taller. Jun 18 2014 In India annual vinca are called Sadaphuli.
As soon as seedlings emerge provide plenty of light on a sunny windowsill or grow seedlings 3-4 inches beneath fluorescent plant lights turned on 16 hours per day off for 8 hours at night. Plant them in rich well-drained soil in full sun after all danger of frost has passed. Dip the cutting in rooting hormone.
Theyre extremely tricky to grow from seed so start with established seedlings.
If you love the look of impatiens but need a carefree flowering annual that thrives in full sun annual vinca is a great choice. Another name for vinca is periwinkle but dont let the name fool you. Vincas are easy to grow annuals with an upright mounding habit. Do the scratch test where you scratch to 1 inch 2-3 cm deep to feel if the soil is dry yet or not.