Funny looking circle underside of geranium leaf

just removed a few lower leaves with this on it...any thoughts?

 

This is rust.what I would do is take off those leaves and destroy them.Keep an eye on the plant and if you get more then do the same with those.Be careful to make sure you don't pick up the spores on your hands so after taking off any affected leaves then make sure you wash your hands.Also be very careful when watering the plant as that can spread the spores round.

If you can keep the greenhouse well ventilated that should help and try not to have too much water on the plants leaves

 

Thanks @Kandy luckily it was only on a couple of the lower leaves so hopefully that is the end of it! (Fingers crossed!!!)

 

I had 70 healthy geraniums in my borders last Summer, by September everyone had Rust. I binned the lot and knowing it could happen again I have stopped growing them.

I think you will be lucky if you don't get any more signs of it but I hope you are.

 

Heck that is awful! Is this the same rust that affects garlic? Had got rust on garlic up on my lotty.

 

@Snorky85 we always have rust when growing garlic but found it only affected the top growth and the bulbs were ok but we have now stopped growing it as Mr Kandy couldn't keep up with eating it and it made his breath stink lol.

I am not sure if these rust problems are all the same type of rust as apart from garlic,pelargoniums/geraniums and hollyhock to name but a few plants and veggies that suffer with it I am not sure if it is the same pathogen

Strongy,sorry to hear that you lost all your plants to rust and it must have been terrible to have to chuck them all away.Luckily when we had the problem nnthe greenhouse over thirty years ago I only had a couple of plants affected and once I had identified the problem through a library book (no internet in those days) destroyed the leaves and allowed mor ventilation in the greenhouse the problem solved itself so I must have caught it early