I live in Ancaster, Ontario, Canada (z 6a). Spring of 2020 I bought a Valencia Orange tree grafted onto US897 rootstock that was about 4ft tall. I have it in a 15g grow bag in a mixture of compost, miracle grow garden soil, and Pro-Mix HP Mycorrhizae, and used Citrus fertilizer as directed from the instructions, and it was super happy last summer and grew amazing and looked super healthy, all the leaves were a deep shiny green all summer. In the winter I put it in my basement under grow lights and it seemed to be ok. It put out a huge bloom, and after the bloom it put out a couple new leaves over the rest of the winter and the leaves stayed a healthy deep green with no signs of disease or damage.

Now the outside daily temperatures are about D: 15°C N: 5°C. About 2 weeks ago I brought it outside cause it’s sunny out now and put it in full shade during the day and brought it into my garage over night. Since being outside over the last couple weeks it has started to put out some new leaves, so this week I decided to move it into a partial shade spot. Since moving it into partial shade I have noticed these brown/bronze spots on the edges of the leaves and in a few leaves around the veins. The brown/bronze is not on all of the leaves on the tree, more on the leaves at the end of the branches. I think it might be sun stress/damage, but it could be a nutrient deficiency or fungus of some sort but I’m not sure and would like to hear any thoughts or opinions. Besides from the brown/bronze on the leaves, the tree seems to be healthy and there are no other signs of damage, stress or disease.

Thanks,

Mike