Does it have to be evergreen? In an area of snow slide I have Annabelle hydrangea and a summer blooming spirea, both of which will grow back from severe pruning if the branches are damaged by falling snow.

Thanks for responding, nhbabs. I am interested in your suggestion, both the hydrangea and spirea are plants I was thinking of for in front of the hopefully evergreen background. I was thinking of using limelight hydrangeas though, or fire and ice hydrangeas. I have never grown Annabelle's, and have heard that they are great except that they flop over after a rain. Has this been a problem for you?

Yes, Annabelle flops, but she is wedged in between other shrubs that provide support, so it really isn't a problem for me. What I like about Annabelle and other H. paniculatas that I can cut her to the ground (and the spireas as well) and she is back to full height, about 4', by bloom time. I don't know how a H. arborescens like Limelight will recover from severe pruning as I have mine in areas where they can grow to their full height.

You might want to look into Little Lime instead of Limelight since it won't get as large.

Thanks for your advise. I think I would like to see 5 to 7 of the same hydrangea with something lower, maybe spirea and perennials interspersed. Of all of your hydrangeas, which do you consider the most showy and successful? I am still hoping for an evergreen background, so the hydrangeas would not get hit directly with snow sliding off the roof. They would be just downslope from that area, but still need to handle late frost following warm days.

If you want evergreens, you can build them little A-frame covers to protect them from the snow. Otherwise, they will be smashed into insignificance.

Are ornamental grasses a possibility?

I planted a rock garden under the eves for my brother in northern Idaho. He has a metal roof which sheds snow from time to time. A few years ago the snow was over four feet deep when it slid off the roof. It piled so high he couldn't see out his sliding glass door or windows. Come Spring, everything was OK.
He has all sorts of wildlife in his remote rural area. Deer, moose, bears and ground squirrels, which makes gardening a bit difficult.
Mike