Q.Cactus rotting and blooming?
So I got an opuntia microdasys about 2 months ago and a week ago its pads fell off. It also started rotting from the top as you can see. I don’t know why, I didn’t give it much water. But I noticed that green something started to grow out of it. Is it going to be a flower? Even though it’s rotting?

Certified GKH Gardening Expert
That soil is extremely overwater. Flowering can be a plants last attempt to reproduce before its death. Cacti do not like to remain moist. That soil can be classified as oversaturated. They dont do well with moderate overwatering but with extreme overwatering this can happen quite easily. You may or may not get seeds from it, but correcting the issue is out of the question at this point. You will have to start over following carefully the cactus care needs.
This article will help: https://www.gardeningknowhow.com/ornamental/cacti-succulents/prickly-pear/growing-prickly-pear.htm