A healthy bigger desert rose can be hang bare root for a month or longer. It might not work on seedlings though and I have not tried hanging mine bare root (just seen videos of it). I think you might have to experiment on growing a few seeds to see what works best for your growing area. I've kept seedlings in small communal plastic containers or clay pots winter time and by spring time they are a few months old ready for transplant into individual pots.
