Why are the insides of my meyer lemons black

Question

Lemon looks fine from the outside, although It ripened must faster than all the others on the tree. But when I cut into the lemon, the entire inside was black

Answer 1

Uh oh. That looks to be the first signs of citrus brown rot. This article will explain what your next steps are: https://www.gardeningknowhow.com/edible/fruits/citrus/citrus-fruit-brown-rot.htm