Is This a Magnesium Deficiency on my Rhododendron Leaf?
The attached photo shows what appears to be some kind of chlorosis on the leaves of one of my rhododendrons. Researching this online, chlorosis can be either an iron or magnesium deficiency.
Iron deficiency is associated with high pH. My plants are in containers of bark, and the pH is quite acidic around 4.5. So I rule out iron deficiency.
Magnesium deficiency seems more likely since I read that low acidic pH can prevent magnesium absorption.
I fertilize these with some Osmocote Plus granules once a year, and about a month ago I additionally started with low does FoliagePro 9-3-6 once a week or every other week. I find it hard to believe that the FoliagePro would not address the magnesium issue, but the pH is pretty low, so....
Should I treat for magnesium deficiency by adding Epsom salt to the fertilizer solution, and if yes then at what dose? I read elsewhere here 1/2 cup of Epsom salt per gallon of water. Should I stop that treatment once the leaves are normal again?
Comments (9)
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