IME, bearded iris are extraordinarily tough plants. I've had forgotten transplants sitting around out of the ground over winter and they've still survived. Ditto with transplants intended for friends/neighbors who never quite got around to picking them up and so they sat in plastic grocery bags (my preferred cheap 'temporary' plant storage method) for months on end. And they still managed to survive, grow and bloom.

It may not be the most ideal planting time but I'd guess the worst you'd encounter planting now is a delayed or missing spring bloom. And maybe not even that. For sure they'd be happier in the ground than in pots. Make sure the ground is not too wet and the rhizomes have good drainage. And I wouldn't mulch - the iris really don't need it and it can lead to rotted rhizomes.

Well, you know for sure they won't grow if you never re-plant them.

HAHAHA.Good point, BBoy.
I guess they have a fighting chance in the ground than in my garage. :)

Thanks Gardengal...You're an angel as well as a wealth of knowledge.