Bryan, many people experiment with zones. I'm fairly cautious myself, but if i'm sure you'll be getting answers from people saying that they are successfully overwintering zone 4, 5, or 6 plants. I've grown a catalpa tree from seed and it overwintered in a container in the ground last year. This year i have it planted into the ground and am hoping it will make it through another winter at least. It's rated zone 4, i believe.

As many people have said here, plants are rated for whatever zones because they haven't been tested in harsher conditions. A lot of plants not considered hardy here are being grown with no problem.

I'm pretty cautious when it comes to shrub/tree zones, first I'll study the tree and its requirements and will ask other local gardeners and this forum if they grow this particular tree.

For other perennials, I'm on the daring side, if they sell it at Holes Greenhouse, I know its hardy.

Sharon

What bothers me is that you go to places like Home Depot, and they sell plants that are only hardy to zone 5 in zone 3.

I know American Hazelnut grows in zone 3, despite being hardy to zone 4, as well as Black Walnut.

I think caution is the right word. Many people here grow roses that are only hardy to zone 5, but wrap them every winter with burlap and mulch them like crazy, and they do fine. You can't beat mother nature, but I guess you can cheat a little bit :)

The info I have is that in Canada zones are actually different than what the US says they are so find a good Canadian zone map.
And FORGET hardiness ratings on plants.... Malva's they say hardy to zone 5.... overwinter here with no protection... And I've had Stripes & Picottees Carnations from Thompson & Morgan zeed company, that they say hardy only in zone 8+... I started from seed last year, overwintered with just a coverage of leaves and they bloomed spectacularly (Sp? LOL) this summer.

If you are pushing the zones when it comes to plants or shrubs, the amount of snow cover you receive in the winter will greatly improve your success.
Most of my plants are beyond my zone. But we usually have tons of snow in the winter.

Shelley

We used to get a lot more snow! 2002/03 was awful with almost no snow all winter and very cold weather. Last winter, it got down to -35*F (-37*C) several times with about 1.5" (4cm) of snow on the ground, then we got 2 feet of snow the next week.

I'm an avid winter enthusiast, so I'm hoping for some good storms this winter.. not only for myself, but also for all the trees I'm planting.

Snowguy...Just curious...What state are you in?

We had the same problem last year. No snow early on, then a little bit, warmish January...then temps dropped to minus 40's and stayed there most of February. There wasn't nearly enough snow protection. And despite the fact I live in AK, the only GOOD use I can think of for snow is as a winter blanket for my green babies...

Barbara in North Pole, AK

I'm in northern Minnesota, and our winters aren't much warmer than North Pole, Alaska. -40*F isn't something just talked about. It happens, along with June/August frosts and very cold summers (2004 being a prime example). For being about 25* in latitude south of you, you wouldn't necessarily know it.

Last winter was very similar here to yours then. We had a lot of ice damage on the lake shores in spring because dry, cold winters crack the ice and the water seeps up from underneath and freezes, pushing the ice sheet into the shores. Luckily the lake was low last winter, so it just pushed up sand, rather than the entire shoreline like it did in '03.

Though I love gardening, I am jealous of you. Alaska is amazing. I've only been to Juneau (and you'll be surprised when I tell you I was there in May for 2 weeks, and it was sunny and 70 every day!).

Snowguy...My neighbors are from Minnesota and they say this is tropical, compared to there! Much drier and we seldom have wind because we're in between two mountain ranges.

I am over 600 miles north of Juneau (as the crow flies). Sounds like my summers are better than yours. We had frost on June 1 last year, but that was unprecedented. Summers are mostly 70's to 80's...Perfect. (AND the 23+ hours of daylight in June/July is really nice too)

But to stay OT, while I'm a flower girl and am not much into trees, I still push the envelope as far as zones. I often read the Canadian forums and then I feel guilty. I'm not Canadian, but Far North in the Lower 48 is still so different. So I take a bit of both and then I wing it...LOL. The old maps put me at Zone 1, but I pretend I am a 3. Like you said, you can cheat a little.