Compared to other plants, periwinkle plants are easier to grow and revive if they are not watered for a few days.
Yet indicating a mysterious illness,the periwinkle plants are suddenly withering and dying.
Watering them does not help in any way.
There were two different periwinkle plants, one with pink/purple flowers and another plant with red flowers,
Both the plants suddenly withered and died during the monsoon.