QuestionI am a Master Gardener with perennial experience but one of my clients has a question about a tree. The Japanese Maple is about 10 - 15 years old and is surrounded by egg sized rocks. In the past few years it seems to be fading by mid summer. It was a wonderful "purple/red" color when it first leafed out and now is pale green with some traces of reddish color. I suspect chlorosis. No insect damage that I can find. Is chlorosis a common disease in Japanese maple? I'm sure it hasn't been fertilized in many years. We live in Michigan and have heavy clay, alkaline soil.
Thanks,
Sue
AnswerI would guess that with the rocks compressing the soil and the air spaces in the soil and the lack of fertilizing, the problem is lack of fertilizer. I would have the soil tested and see what is lacking--also pay attention to the pH. Not knowing what kind of rocks or the depth of the layer of rock it is hard to say much about those. Some rocks are limestone based and will over time through rainfall events change the ph of the soil and/or tie up minerals.
