Peach tree with red leaf spots and dropping leaves

Question

I have a young peach tree I purchased from a nursery, it was growing really fast when I transplanted it to a pot, but suddenly it stopped growing and a side of the branches is color red as well as the leaves, which are also curled to the inside. At first I thought it was nitrogen deficiency so I applied a fruit trees fertilizer which is 15-5-20. What could be happening to the tree?

Answer 1

I suspect water deficit (drought stress). Adequate watering is important. Or possible it lost roots in the transplanting and is unable to take up water until it starts to put out new roots.