How can I plant annual perwinkles to encourage their natural duplication?
How Do I Plant Annual Periwinkles to Encourage Their Natural Duplication?
Certified GKH Gardening Expert
Typically, this flower will reseed on its own. You can encourage reseeding by avoiding deadheading, planting the original plants in a sheltered location and laying down a bit of protection in the fall, such as straw or a bit of mulch.