Vinca turning yellow.....
I have planted some Vinca (annuals) and the leaves are turning yellow. They are planted in a bed, 1/2 of the plants get full morning sun and the other 1/2 gets partial morning sun (some shade). They are all turning yellow (varying stages, but the majority have at least a few yellow leaves).
It seems to be growing, but I am concerned that I will lose all of it! We have had a very unusual amount of rain this Spring... could it be that they are receiving too much water?
What is causing these very durable plants to turn yellow??