Just This Season, The Lemons On My Lemon Tree Have Turned Brown, But They Are Still Juicy And Taste Good. Why Are They Brown?

Question

The lemon tree is about ten years old and has always had regular looking lemons – this year they have started off yellow but quickly turned brown

Answer 1

It could be rust mite damage or citrus melanose. Here is more:

https://www.gardeningknowhow.com/edible/fruits/citrus/citrus-mite-problems.htm

https://www.gardeningknowhow.com/edible/fruits/lemons/pests-of-lemon-trees.htm

https://www.gardeningknowhow.com/edible/fruits/citrus/citrus-melanose-fungus.htm