I think I read somewhere they don't turn yellow like the ones you buy in the store when ripe. They are ripe when they only get a blush of yellow. Some one correct me if I am wrong. :o)

Mine are doing the same thing, last year they were nice and plump and yellow, this week when I went to pick some that were yellow, they were rotted on the bottom.
I'll be looking foward to some answers.
Happy Gardening
Carmen

The same thing has happened to me.

Last year they were ripe and yellow like a regular lemon. They never turned that dark yellow-orange like what I've seen in the store. Of course, they also weighed five times as much too.

This year I have had a lot of aborted fruit. My experience is that fungal infections scab over, then fall off wnd open little holes in the skin, and then beetles and rot get in there. This turns them dark yellow.

I start to use my meyer lemons from the time that they are green to the time that are fully yellow, they are a little bit more tart when green but still delicious flavor!

I needed a lemon for my raw fresh zucchini salad and I was happy to find out that they are as good as I remember them.

Silvia

Recently I was given a large green Myers lemon from the owners tree. I have my own key lime tree so normally that's what I digest. I left the huge (4 x the size of my avg key lime ) Myers lemon on my kitchen counter and it only turned a light yellowish/light green color, but no rotting.
Have recently started freezing these lemons/limes after I read about the idea which came about upon some chef somewhere learning that 90% of the nutrients that fight all kinds of cancers/ailments are contained in the rind. So I now regularly grate up an entire frozen lemon or lime and sprinkle it on most foods, - the taste is great also ! Just passing along my tip of the day ! ( smile )