Hello, I replanted my Lemon tree. This is my first go at it. I grew it from a seed from the grocery store lemon. I live in Canada Ontario. Can anyone identify what took place with my tree? I cut of all the leaves that looked like this in fear that it was a disease. The tree has mostly been inside and we have been having nice weather. The leaves are dark green and I left the tree outside for 48hrs then I came back to this.
That is an odd colour and pattern... I don't recognize it as a nutrient deficiency, infection, or pest... could it be sunburn? Do they match where the sun was on it the longest?
My guess would be either sunburn or, more likely, mesophyll collapse as a result of the plant's move outdoors. Citrus: Identifying Diseases and Disorders of Leaves and Twigs—UC IPM
I vote for sunburn. My mandarins got similar symptoms after being already several weeks outdoors, only then, when there was a heat wave, constantly clear sky with scorching sun, and temperatures at the hot spot near the south wall of my house, where I keep my warm weather loving plants, rose above 30ºC.
