Why do wild violets not flower?
They are planted in various parts of the garden in good soil, not soggy with some leaf matter, both in sun/shade. The leaves are big and healthy but alas no flowers.
Certified GKH Gardening Expert
There may be to much Nitrogen in the soil. This will cause lush greens and no flowers.
You can add phosphorous by using Bone Meal.
Here are a few links for you.