Vinca Flower Winter. Vinca minor common periwinkle is a good choice as its a very hardy variety. In these climates it generally survives the winter.
Annual vinca is invincible to most pests but it can succumb to stem and root rot caused by Phytophthora a soil- and water-borne fungal-like microorganism. The second type summer-flowering vinca has the botanical name Catharanthus roseus. Jan 12 2020 Add at least 4 inches of loose organic mulch such as wood chips straw or leaf compost in November to winterize your vinca.
Its rare that such an infection happens in pots because usually drainage is much better than in the ground.
The best preventive measures are to avoid overwatering and provide good drainage. They dont climb like ivy but spread low across the ground. For greater protection from frost freezes and snow completely cover the foliage in 5 to 6 inches of loose mulch. Vinca Vinca minor also called myrtle and common periwinkle grows in US.