We have a two year old Meyer Lemon that stayed indoors in the winter and is now on the screen porch. Last year it produced 3 very nice lemons. This year I have been using citrus fertilizer and the tree has numerous flowers and fruit.

However, as you know, when the fruit is just starting to grow the lemon is a dark shiny green. Very recently several of the lemons have stopped growing and turned a light brownish yellow color and become rock hard.

Is this lack of water, too much water or what am I doing wrong?

Thanks for the help.