Answer: This spirea naturally undergoes a color change from spring into summer, beginning a brighter yellow green and maturing to what is described as lime green followed by good fall color in oranges and reds. I think this description of summer color is in contrast to normal spirea which is more of a blue-green. Also, the color can change somewhat depending on temperatures and the amount of sunlight the plant receives. I think what you are seeing is probably normal.
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