I have a brick planter that's 4 bricks high that has been fine for tulips, daylilies, various spring bulbs. There's also dianthus, primula, and salvia that seem to be coming along just fine.

My strawberry patch is in a 10 inch high cedar raised bed and they've come through the winter just fine also.

I have my strawberries in raised vege planters. The planters are about 18 inches high and the strawberries survive just fine. I am zone 2b....Jean

I also have raised beds, strawberries come thru fine, if they have snow cover or straw, we get alot of drying winter wind. I also have tulips and a cutting garden in raised beds. C

I'm not in Z3 but I do know that the amount of snow cover can make a big difference in where you can grow some plants. For example, with adequate snow cover to provide extra insulation against repeated freeze/thaw cycles which cause heaving you can grow a lot of plants in a raised bed (or even overwinter in pots) that you couldn't otherwise. So part of this will depend on what your normal winter snow cover is.