Containers of hardy plants generally do not require much in the way of special protection over the winter in a zone as mild as 7. There are some exceptions - plants which may prefer very dry soil conditions might fair better if protected from the worst of the rains, etc. But clematis, hostas and other hardy perennials, trees and shrubs can be left out through the winter in a zone 7, provided the container is of sufficient size. If your garage is unheated, then the plants can go back outside now. No need to to do this gradually unless the garage temps have been consistantly above 50F. If a sharp frost or sudden cold spell is predicted, then cover the pots at night. Grouping them together will also afford some additional protection. My nursery is located in a zone 7b and operates all year long. Containerized hardy plants are left outside all year as well, including those as small as gallon sized perennials and 4" groundcovers. Winter damage is minimal and is usually associated with too much wet/too moisture retentive a container soil rather than cold damage. Wholesalers in the area also grow their containerized crops outdoors all winter as well.

Mindy, I've often overwintered potted lilies, but in my unheated garage. I grew lilies in crates this year for cutting, and I am going to try to overwinter them also, still in the crates. I don't know about that 60 degree temp, though. I would think that would bring the lilies out of dormancy. Sorry, can't help with the caladiums. I've never grown those - although I do know I can't overwinter potted dahlias in the garage. I don't know how similar (or not!) a caladium would be to a dahlia! :) Dee

I wouldn't risk leaving them in a garage. Sinking the pots would be better. But if you're going to the trouble to sink the pots, why not just go ahead and plant them if you've planned out the spot for them anyway. It's not too late and they're incredibly tough - I left some exposed in a pile in the garden over a northern MN winter. They all survived and bloomed without missing a beat.

Assuming they're bearded iris (the most common kind in Texas): I wouldn't cut the leaves off, & if possible I'd put them in pots; it'll be less stressful on the plants. If it isn't possible to plant them in pots, they'll probably be fine stored in a box, but it will likely take another year after you do plant them before they have the energy to bloom.