Close up

Not a disease. The rather coarse stippling reminds me of damage from leafhoppers. (If so, you might find them on the undersides of the leaves.) Seldom an important problem, at least where I live.

is seems to lack vigor ... for a mint ...

which somehow.. always attracts vermin ... how do they know.. what plants are stressed???

and i cant makes head nor tails out of all sand in one pic ..... and then a pot ...

my mints also had some bug.. that came up to the bottom.. and seemed to chew or suck on one layer of the cell.. stunting that layer but not really killing a leaf.. in extreme heat those areas might brown ...

i never found a bug.. and never really cared.. as it was an invasive weed where it stood ...

it really doesnt make a difference to its mintiness ... but its make them ugly.. and who wants to put something ugly in their mouths ...

ken

I've noticed something chewing here and there on a few plants I have inside, so leaf hoppers could be the culprit, but during the warm months I keep all of my potted plants outside, and this specific problem has never occurred on any of them.
The peppermint plant did dye back from an unexpected cold snap, and the sand was just a backdrop on which I placed one of the infected cuttings for the photo.
Thank you very much for the input