why are my wild violet leaves yellowing?

Question

I have these planted in many locations around my yard, in garden areas, but the batches in my tree ring are getting yellowing leaves. It started with one plant and is now moving to others. I’ve attached a picture of the plant and also the tree ring area. This is a mostly shady area, it does get minimal sun. All other areas that I have these are thriving.

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Answer 1

You may want to check your violets for spider mites, which can be treated with the application of neem oil. Here are a couple helpful articles:
https://www.gardeningknowhow.com/ornamental/bulbs/violet/wild-violets-care.htm
https://www.gardeningknowhow.com/plant-problems/pests/insects/spider-mite-treatment.htm
https://extension.illinois.edu/blogs/extensions-greatest-hits/2007-08-28-yellow-leaves-can-indicate-plant-problems

I had some plants that looked like that in mid summer and I just left them. After a while it corrected itself. It was probably a nutrient deficiency.

I might mention too that those plants are competing for nutrients with the tree. In fact, I'm concerned about that smaller ring. Piling dirt up on top of the tree's feeder roots can prevent oxygen from getting to the roots. The tree will usually decline in health over time. See the notation in this article:

https://www.gardeningknowhow.com/ornamental/trees/tgen/planting-garden-beneath-trees.htm