Q.fertilizing a lemon tree
My lemon tree leaves are pale green. It’s 2 years old and although this year it had about 1 dozen lemons on it, the lemons had no juice. It’s about 4 ft high.
I've listed several great articles for you that should help you pinpoint the issues and help you grow lots of lemons!
https://www.gardeningknowhow.com/edible/fruits/lemons/how-to-grow-a-lemon-tree.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/hand-pollinating-lemons.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/lemon-tree-not-fruiting.htm
https://www.gardeningknowhow.com/edible/fruits/lemons/learn-about-fertilizer-for-a-lemon-tree.htm