Answer: Foliage color can be affected by a variety of factors but is often soil-related. The best way to diagnose that is to have your soil tested. Your local county extension can help you with the testing and interpreting the results. They may also be able to examine the leaves and diagnose it that way. If it is related to low nitrogen, it is so late in the season now that you would wait until spring to fertilize to supplement that. If it is related to inappropriate pH or lack of a minor nutrient, you might be able to supplement now. If it is a due to a disease or pest issue the treatment and timing would depend on the specific cause. It is also possible that you are seeing new growth with a naturally slightly different color due to lack of maturity or a difference in lighting or other cultural factor. This type of symptom is very difficult to diagnose long distance so I would suggest you consult with your county extension or/or professionally trained nursery staff. They may appreciate photos of the overall plant and close-ups of the foliage and possibly a sample or two. Good luck with your plant!
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