Lemon tree problem

Question

I have a container lemon tree that has black spots on the underside of the leaves and the leaves have a “withered” look.

Answer 1

I would check your lemon tree for citrus thrips - black spots on the underside of leaves are typically a hallmark of thrips.
https://www.gardeningknowhow.com/edible/fruits/citrus/controlling-citrus-thrips.htm

For more information on growing lemon trees, please visit the following link:
https://www.gardeningknowhow.com/edible/fruits/lemons/how-to-grow-a-lemon-tree.htm