Vinca is a widely used bedding plant to add bright color to full sun locations in the garden. First, let’s clear up a bit of confusion about the name: The annual vinca we are talking about is also known as Periwinkle. It is a very colorful summer annual that does not come back after Winter. The other kind of Vinca is a groundcover that likes shady areas and does come back each year – but it is only colorful when it blooms with its blue flowers in early Spring.