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Lemon trees leafs turning yellow #834289
Asked June 07, 2023, 11:03 AM EDT
Chisago County Minnesota
Expert Response
Thanks for the question. Is this strictly an indoor tree or do you move it outside in the summer and then back inside during the winter? Also if possible, please send me some pics of the tree: one of the whole tree and then a couple close-ups of the leaves. Many thanks.
Thanks for the question.
Yellowing of lemon tree leaves can be a sign of various issues, including chlorosis (see the leaf in image 20230608). That leaf shows all the typical symptoms of chlorosis: yellow background and green leaf veins. The underlying cause is a breakdown of chlorophyll. Here are some things to consider:
1). The yellowing could reflect a lack of essential nutrients such as iron, magnesium, and/or nitrogen. Among citrus trees the most common cause of chlorosis and leaf yellowing is either an iron deficiency or a nitrogen deficiency. I note that you have used ironite to address this issue. This contains iron in what is termed a “chelated” form. This is a form of iron that is retained by plant tissue. I cannot explain why the ironite did not appear to have some mitigation of the yellowing. But if the chlorosis is due to a nitrogen deficiency, then it would be expected that ironite would not remedy the situation.
2). Most citrus trees, including lemon prefer a slightly acidic soil with a pH range of 6.0 to 6.5. Have you checked the pH of the soil in which the tree is growing?
3). Root rot is common in lemon trees due to overwatering. If this condition occurs then there is impaired nutrient uptake leading to leaf yellowing. The soil should dry out slightly between waterings, but don’t let it become bone dry.
4). Finally, stresses due to excessive sunlight or insufficient light can lead to lead discoloration. Provide adequate sunlight and protection form extreme temperatures.
With these thoughts in mind, take a look at the following paying special attention to remedial steps that you could take:
https://www.independenttree.com/chlorosis/
https://acmg.ucanr.edu/files/204721.pdf
https://www.youtube.com/watch?v=QXDrW3Q4XnQ
https://myplantin.com/blog/lemon-tree-leaves-turning-yellow
https://www.youtube.com/watch?v=qKutvJh3sTw
Good luck. Please get back to us with any additional questions.