Spots on my mint leaves
I've recently grown some mint from cuttings and I have noticed they are developing some white and brown spots.
I am a little worried as I was planning to sell them, many of the cuttings seem fine but I'm worried it will spread.
Upon checking my adult plants I can see they have the same spots.
Is this a soil deficiency or a pest infestation? I did find a caterpillar on one plant which I removed, I checked the plants and can't see anymore.
The cuttings are in Westland John Innes no2 and the adult plants are in a generic multi purpose compost, could the compost be the issue?
Any advice would be greatly appreciated!