Q.lemon tree keeps losing leaves
Plenty of unripe fruit but the leaves keep falling off. New leaves coming in on top. Live in zone 9, and 85 degrees here.

Certified GKH Gardening Expert
It is likely stress related, possibly from the heat. Make sure it is getting plenty of water and a little fertilizer may help as well. Leaf drop is a common problem in both lemon and lime citrus trees. Here is an article that you may find helpful: https://www.gardeningknowhow.com/edible/fruits/lime/lime-tree-leaf-drop-why-a-lime-tree-is-losing-leaves.htm