Interesting. Do you mist the trays. I use small bowls of potting mix. What do you do when the roots and plantlet form?

Many succulents will grow from the leaves, and they should be kept on dry side. So rooting them on paper towels usually works well. They will root on glas, plastic trays or just about anything - obviously, on top of or just touching the potting mix as well. 'Sprouts' in your photos need more light - getting very etiolated :) But good light conditions are not always available...

Are those on pink tray sempervivums? If so, they do not need to be rooted. What looks like a stem is a stolon that offset was attached to mother plant. It could be cut off, leaving just a short stub to stick into a fast draining mix - best if grown outdoors (sempervivums are very hardy). Roots will grow directly into it from the base of rosette, they do not grow from a stolon ( occasionally yes, but very few).

thanks so much! rob, I soak the trays then leave them to become bone dry. they actually thrive like this. I've tried misting them, but they just seem to rot. I plant them in a gritty mix when roots and plantlets form. rina, I know that they need more light, but there isn't much I can do about that. thanks for the help people!

Apologies if I'm missing something obvious here, but what do you mean by "soak the trays"? For some reason, my only interpretation is that you basically take the whole thing and dunk it in a bucket or something? But surely this would lead to more rot-related issues than misting? Am I simply not getting the picture here, or do you have some sort of magical dunking method? Superior trays, perhaps? Or could it be perfect paper towels? Either way, I'd love to know. :)