1)any & all techniques you mentioned will work... 2) soil temp for rooting depends on species you are working with but as a general rule the SOIL temperature needs to be in the 60-70F range for rooting..... 3)storage needs to be above 40F OR the soil must be damp when the soil freezes

Thank you very much, yiorges.. Do I need to/should I monitor the temp in the garage if I move them all there, to be sure it stays above 60 degrees until I see they've rooted sufficiently?

So far I've done all woody shrubs that I've read can be propagated as semi-hardwood, but am going to add a bunch of holly as soon as I can, and then leave them in their starting pots/trays over the winter (probably let them freeze, or near it, as you described), and expect they'll continue the process in Spring. Does it sound as if I'm on the right track?

Thanks again for any/all advice/input...