Potted lemon trees leaves are drying out looks dead but roots an stems are fine why

Question

We are in cold winter zone plant is indoors

Answer 1

Temperature, lack of sunlight and improper watering are common reasons for leaf drop.
This article will help you adjust the conditions for your Lemon Tree.
https://www.gardeningknowhow.com/edible/fruits/citrus/growing-citrus-trees-indoors.htm