Unidentified yellow spots on leaves

Hello all!

I was weeding a mint bed, mainly removing mainly what I think is epilobium tetragonum.

I noticed quickly that almost all of them had yellow dots, tiny bumps, on their lowest leaves.

I also found, around one of the plants, the same yellow dots on the earth/stone nearby. Yet, this is not paint!

Does anyone know what these yellow dots could be?

Damien

My guess is some sort of fungal fruiting body, like a 'rust'. They can be fairly common on older leaves, particularly in drier conditions I believe. I suspect that they have been falling off the leaves as they mature. I wouldn't worry too much about it. I think there is a rust that affects mint - are your plants sprouting yet? How do they look?

Thanks for your answer!
The mint has emerged, yes, but is not affected by the "rust".

I am still unsure: I live in Oslo, winter is barely over, and these epilobium tetragonum have thus sprouted very recently. Could a fungi develop so quickly, and so specifically on these plants, that are still babies, full of energy, at that time of the year?!