Hi Matt...I have roses, including minis, planted right next to the road around my mailbox. I also have around 150 or so more planted on the hillside running alongside the road.
Amongst all these roses I also have daylilies, irises, tulips, clematis, and other assorted companions intermingled amongst the roses and none have suffered any ill effects.

Mostly the road crews use sand when it gets bad, but when it gets very icy, they do resort to using salt. I've had roses planted here for 2 years, and I haven't lost any yet.
-terry

It depends on how much salt they use and how far up on your lawn they plow the snow. If your lawn shows no affects from winter's snow or salt, your rose should be OK also. If your lawn has dead grass from the snow or salt residue, you may want to either rethink planting it there or place it in a large pot that you can move away from the area.
Another concern is the weight of the plowed snow on the rose. Plowed snow is compacted, often slushy, and can get quite deep and heavy along the curbs and parkway. Chances are the area will be covered with deep snow all winter so if nothing else, provide something to cover it with that'll take a heavy snowload without collapsing.
I tried Bonica along the street at my driveway. It was covered with snow all winter and required severe pruning each spring. It never grew very large which was probably due to the road salt.

Here's an idea of how far from the road I set back my plants when they were first planted. This was Year One and taken about 3 months after planting...of course now everything is matured and I've added many more perennials to the mix.

Last year was a bad winter of continual snow and ice, and I didn't have any problems with the snowplow or the weight of the snow breaking any bushes because they are planted far enough back from the road to be protected.

{{gwi:313088}}

A mailbox planting will be right next to the road and subject to a heavy suffocating snow load unless we don't have much snow.
The Bonica I mentioned was just two feet from the curb.

You can barely see my mailbox planting in the pic above. I have several roses planted, along with iris, daylilies, clematis, salvia, and Japanese grass.

My mailbox is also next to the driveway, where it gets additional snow from my DH's plow in addition from the county plow. Thomas Affleck, Earth Song, and several minis
such as Incognito, Dr. John Dickman, and Memphis King continue to thrive and bloom every year without any ill effects.

So, have I convinced you enough yet, Matt? I don't think 'one' mini is enough, tho. You should add to that rose order we were emailing about earlier last week :),
-t

You really seem to be enjoying this Terry. I've already ordered two WS2000 from RU because of you. The mini (Roxy) would be an addition to the order I've already placed with Palatine.

The mailbox is very close to the street...about 1'. Typically, with plowing and driveway shoveling the area gets about 3' of snow, sometimes more. So would I have to put a crate over it to ensure it's not smothered?

I thought snow provides good insulation for roses??? If so, how much is too much? Does it depend of the "wetness" of the snow? That being said, light snow can become very heavy with a winter rain.

I should probably forget the whole thing, but I've been getting a little obsessed lately.

Haha...two? My work here is done...

Seriously, why not set them back from the mailbox? My box juts right up next to the road also, so my plantings are in back of it and slope towards the house. I'll try to get you a pic tomorrow and e-mail it to you so you can see what I'm talking about. But I feel one eeeny mini may not be enough...

Snow is a great insulation for roses...I'm always glad to see it come when I know it's going to get into the low teens and minus digits since I don't winter protect at all...my only method of winter protection is just oak leaves that blow in and the oak mulch at their feet. However, big huge 'snow boulders' dumped on them from passing snow plows can break canes. Since I've set mine back a couple of feet from the road, it hasn't proven to be a problem.

Try placing an upside down milk crate over the bushes. They'll still be open to the weather and moisture but the crate will keep the heaviest snow and "snow boulders" off the rose plants.