How cold does your unheated garage get would you say?--As you say, concern is NOT with the snow or sleet but cold temps for containerized plants. I overwinter my containerized 'cold' and 'subtropicals' in a cold (40-60F) but frost free garage (glass windows/doors on the front face due south so there's quite a bit of sun). If your garage is just as cold as outside, I would put them in that protected NE exposure you described but bury the pots in a bed of mulch. By the way, I grow the Dwarf English Box and it makes for one absolutely gorgeous formal hedge--good luck with that knot garden!

PS., Attached is a pic taken from back window of the storm that "missed" us (we ended up with six inches of snow.)

Here is a link that might be useful:

Thanks njoasis!

My garage was 42 degrees last night when it was 16 outside.
It has a SE exposure and is fairly sheltered. The garage door has windows.
There is a retaining wall and the concrete driveway which tends to hold in some heat.

I decided to put the plants in the garage in an area so that when it is above freezing I can open the garage door and the plants can get sun.

Just keep them in the garage and make sure they are damp. FYI, I have a boxwood hedge next to my cistern. We are at 3,200 feet and those plants are exposed to cold, snow, and ice off and on beginning in late October and going through til it thaws out in March. As a mater of fact, the bottom portions become boxwood-sicles because the spray from the overflow of the cistern splashes onto them and freezes.
I just love them because they are so hardy and give me some green in winter. The downside is they are also close to my creek-side deck and boxwoods do have a sorta cat pee smell.

Thanks coorscat!

The plants seem to be doing fine. I will make sure they are kept damp.
The garage temperature is staying around 40 to 44 degrees.
Hopefully, they will not suffer too much transplant shock.

I think you and your boxwoods are going to be just fine!

Those conditions are fine! Yes, they do have that certain aroma--been described as anything from musky, pee, body odor, fertilizer, to wet dog... On the plus side, deer HATE Box. Some people hate the smell and some people are led to recall fond childhood memories. I find it kind of earthy and think of Spring.

I was able to open the garage door for a couple of hours today. The plants received about two hours of sun.
So far -So good!

I have some dwarf boxwood near my front door and after it rains they do smell like cat pee! I still love them though!

Box are, without a doubt, most superior as a formal hedge. I love'em too! Are you growing herbs as well? �Not really too well informed on "Knot gardens". What exactly are they? I also love herbs because guess what...deer hate them. Love especially rosemary, bay, lemon verbena, LAVENDER, chamomile, greek oregano, sage, and thyme.