Answer: Using Holly-Tone will effectively lower your soil's pH which is important for your euonymus so you got good advice and I'm glad you're following through. In my experience, these shrubs turn reddest when grown in full sun all day long. In a shady spot, the coloring will be reduced. If yours are not in all day sunshine, that might be the problem. If they are in full sun, the only other thing that might prevent the autumn color change is that they are not experiencing the cold temperatures required for the leaves to turn colors. I realize it gets cold in Bangor, but is it possible your shrubs are being sheltered by nearby buildings or trees or larger shrubs? You didn't mention whether or not you've pruned your shrubs. Prune in the spring to encourage lots of new growth which should turn the color you expect when the temperatures change in fall.
Best wishes with your shrubs!
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