Begonia leaf cuttings in ziplock bags

I’ve just taken leaf cuttings of Begonias as I saw someone on instagram doing them already and thought I’d get started on them early and then can always do some more later on if I need to.

Last year I did them in July, I cut across the leaf veins and left the leaf whole to place on compost and perlite mix but they got infected with a fungi which was very quickly taking over so I salvaged them by taking them out of the compost and putting them in ziplocks, I then didn’t have time to do them for about two weeks and so when I finally got to them they had started rooting in the bag.

So that’s what I’m trying this time; as they take up less space and I can keep an eye on if they are rotting.

I cut across the leaf veins put the whole leaf in the bag, mist, drain excess water and close up. I’ll then open once in a while to get fresh air through.

Question is where should I put them? Sit them on the heat bench? Or put them in the grow room that have lights?